accessibility.src.js 99.3 KB
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224 1225 1226 1227 1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 1240 1241 1242 1243 1244 1245 1246 1247 1248 1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263 1264 1265 1266 1267 1268 1269 1270 1271 1272 1273 1274 1275 1276 1277 1278 1279 1280 1281 1282 1283 1284 1285 1286 1287 1288 1289 1290 1291 1292 1293 1294 1295 1296 1297 1298 1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 1309 1310 1311 1312 1313 1314 1315 1316 1317 1318 1319 1320 1321 1322 1323 1324 1325 1326 1327 1328 1329 1330 1331 1332 1333 1334 1335 1336 1337 1338 1339 1340 1341 1342 1343 1344 1345 1346 1347 1348 1349 1350 1351 1352 1353 1354 1355 1356 1357 1358 1359 1360 1361 1362 1363 1364 1365 1366 1367 1368 1369 1370 1371 1372 1373 1374 1375 1376 1377 1378 1379 1380 1381 1382 1383 1384 1385 1386 1387 1388 1389 1390 1391 1392 1393 1394 1395 1396 1397 1398 1399 1400 1401 1402 1403 1404 1405 1406 1407 1408 1409 1410 1411 1412 1413 1414 1415 1416 1417 1418 1419 1420 1421 1422 1423 1424 1425 1426 1427 1428 1429 1430 1431 1432 1433 1434 1435 1436 1437 1438 1439 1440 1441 1442 1443 1444 1445 1446 1447 1448 1449 1450 1451 1452 1453 1454 1455 1456 1457 1458 1459 1460 1461 1462 1463 1464 1465 1466 1467 1468 1469 1470 1471 1472 1473 1474 1475 1476 1477 1478 1479 1480 1481 1482 1483 1484 1485 1486 1487 1488 1489 1490 1491 1492 1493 1494 1495 1496 1497 1498 1499 1500 1501 1502 1503 1504 1505 1506 1507 1508 1509 1510 1511 1512 1513 1514 1515 1516 1517 1518 1519 1520 1521 1522 1523 1524 1525 1526 1527 1528 1529 1530 1531 1532 1533 1534 1535 1536 1537 1538 1539 1540 1541 1542 1543 1544 1545 1546 1547 1548 1549 1550 1551 1552 1553 1554 1555 1556 1557 1558 1559 1560 1561 1562 1563 1564 1565 1566 1567 1568 1569 1570 1571 1572 1573 1574 1575 1576 1577 1578 1579 1580 1581 1582 1583 1584 1585 1586 1587 1588 1589 1590 1591 1592 1593 1594 1595 1596 1597 1598 1599 1600 1601 1602 1603 1604 1605 1606 1607 1608 1609 1610 1611 1612 1613 1614 1615 1616 1617 1618 1619 1620 1621 1622 1623 1624 1625 1626 1627 1628 1629 1630 1631 1632 1633 1634 1635 1636 1637 1638 1639 1640 1641 1642 1643 1644 1645 1646 1647 1648 1649 1650 1651 1652 1653 1654 1655 1656 1657 1658 1659 1660 1661 1662 1663 1664 1665 1666 1667 1668 1669 1670 1671 1672 1673 1674 1675 1676 1677 1678 1679 1680 1681 1682 1683 1684 1685 1686 1687 1688 1689 1690 1691 1692 1693 1694 1695 1696 1697 1698 1699 1700 1701 1702 1703 1704 1705 1706 1707 1708 1709 1710 1711 1712 1713 1714 1715 1716 1717 1718 1719 1720 1721 1722 1723 1724 1725 1726 1727 1728 1729 1730 1731 1732 1733 1734 1735 1736 1737 1738 1739 1740 1741 1742 1743 1744 1745 1746 1747 1748 1749 1750 1751 1752 1753 1754 1755 1756 1757 1758 1759 1760 1761 1762 1763 1764 1765 1766 1767 1768 1769 1770 1771 1772 1773 1774 1775 1776 1777 1778 1779 1780 1781 1782 1783 1784 1785 1786 1787 1788 1789 1790 1791 1792 1793 1794 1795 1796 1797 1798 1799 1800 1801 1802 1803 1804 1805 1806 1807 1808 1809 1810 1811 1812 1813 1814 1815 1816 1817 1818 1819 1820 1821 1822 1823 1824 1825 1826 1827 1828 1829 1830 1831 1832 1833 1834 1835 1836 1837 1838 1839 1840 1841 1842 1843 1844 1845 1846 1847 1848 1849 1850 1851 1852 1853 1854 1855 1856 1857 1858 1859 1860 1861 1862 1863 1864 1865 1866 1867 1868 1869 1870 1871 1872 1873 1874 1875 1876 1877 1878 1879 1880 1881 1882 1883 1884 1885 1886 1887 1888 1889 1890 1891 1892 1893 1894 1895 1896 1897 1898 1899 1900 1901 1902 1903 1904 1905 1906 1907 1908 1909 1910 1911 1912 1913 1914 1915 1916 1917 1918 1919 1920 1921 1922 1923 1924 1925 1926 1927 1928 1929 1930 1931 1932 1933 1934 1935 1936 1937 1938 1939 1940 1941 1942 1943 1944 1945 1946 1947 1948 1949 1950 1951 1952 1953 1954 1955 1956 1957 1958 1959 1960 1961 1962 1963 1964 1965 1966 1967 1968 1969 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025 2026 2027 2028 2029 2030 2031 2032 2033 2034 2035 2036 2037 2038 2039 2040 2041 2042 2043 2044 2045 2046 2047 2048 2049 2050 2051 2052 2053 2054 2055 2056 2057 2058 2059 2060 2061 2062 2063 2064 2065 2066 2067 2068 2069 2070 2071 2072 2073 2074 2075 2076 2077 2078 2079 2080 2081 2082 2083 2084 2085 2086 2087 2088 2089 2090 2091 2092 2093 2094 2095 2096 2097 2098 2099 2100 2101 2102 2103 2104 2105 2106 2107 2108 2109 2110 2111 2112 2113 2114 2115 2116 2117 2118 2119 2120 2121 2122 2123 2124 2125 2126 2127 2128 2129 2130 2131 2132 2133 2134 2135 2136 2137 2138 2139 2140 2141 2142 2143 2144 2145 2146 2147 2148 2149 2150 2151 2152 2153 2154 2155 2156 2157 2158 2159 2160 2161 2162 2163 2164 2165 2166 2167 2168 2169 2170 2171 2172 2173 2174 2175 2176 2177 2178 2179 2180 2181 2182 2183 2184 2185 2186 2187 2188 2189 2190 2191 2192 2193 2194 2195 2196 2197 2198 2199 2200 2201 2202 2203 2204 2205 2206 2207 2208 2209 2210 2211 2212 2213 2214 2215 2216 2217 2218 2219 2220 2221 2222 2223 2224 2225 2226 2227 2228 2229 2230 2231 2232 2233 2234 2235 2236 2237 2238 2239 2240 2241 2242 2243 2244 2245 2246 2247 2248 2249 2250 2251 2252 2253 2254 2255 2256 2257 2258 2259 2260 2261 2262 2263 2264 2265 2266 2267 2268 2269 2270 2271 2272 2273 2274 2275 2276 2277 2278 2279 2280 2281 2282 2283 2284 2285 2286 2287 2288 2289 2290 2291 2292 2293 2294 2295 2296 2297 2298 2299 2300 2301 2302 2303 2304 2305 2306 2307 2308 2309 2310 2311 2312 2313 2314 2315 2316 2317 2318 2319 2320 2321 2322 2323 2324 2325 2326 2327 2328 2329 2330 2331 2332 2333 2334 2335 2336 2337 2338 2339 2340 2341 2342 2343 2344 2345 2346 2347 2348 2349 2350 2351 2352 2353 2354 2355 2356 2357 2358 2359 2360 2361 2362 2363 2364 2365 2366 2367 2368 2369 2370 2371 2372 2373 2374 2375 2376 2377 2378 2379 2380 2381 2382 2383 2384 2385 2386 2387 2388 2389 2390 2391 2392 2393 2394 2395 2396 2397 2398 2399 2400 2401 2402 2403 2404 2405 2406 2407 2408 2409 2410 2411 2412 2413 2414 2415 2416 2417 2418 2419 2420 2421 2422 2423 2424 2425 2426 2427 2428 2429 2430 2431 2432 2433 2434 2435 2436 2437 2438 2439 2440 2441 2442 2443 2444 2445 2446 2447 2448 2449 2450 2451 2452 2453 2454 2455 2456 2457 2458 2459 2460 2461 2462 2463 2464 2465 2466 2467 2468 2469 2470 2471 2472 2473 2474 2475 2476 2477 2478 2479 2480 2481 2482 2483 2484 2485 2486 2487 2488 2489 2490 2491 2492 2493 2494 2495 2496 2497 2498 2499 2500 2501 2502 2503 2504 2505 2506 2507 2508 2509 2510 2511 2512 2513 2514 2515 2516 2517 2518 2519 2520 2521 2522 2523 2524 2525 2526 2527 2528 2529 2530 2531 2532 2533 2534 2535 2536 2537 2538 2539 2540 2541 2542 2543 2544 2545 2546 2547 2548 2549 2550 2551 2552 2553 2554 2555 2556 2557 2558 2559 2560 2561 2562 2563 2564 2565 2566 2567 2568 2569 2570 2571 2572 2573 2574 2575 2576 2577 2578 2579 2580 2581 2582 2583 2584 2585 2586 2587 2588 2589 2590 2591 2592 2593 2594 2595 2596 2597 2598 2599 2600 2601 2602 2603 2604 2605 2606 2607 2608 2609 2610 2611 2612 2613 2614 2615 2616 2617 2618 2619 2620 2621 2622 2623 2624 2625 2626 2627 2628 2629 2630 2631 2632 2633 2634 2635 2636 2637 2638 2639 2640 2641 2642 2643 2644 2645 2646 2647 2648 2649 2650 2651 2652 2653 2654 2655 2656 2657 2658 2659 2660 2661 2662 2663 2664 2665 2666 2667 2668 2669 2670 2671
/**
 * @license Highcharts JS v6.2.0 (2018-10-17)
 * Accessibility module
 *
 * (c) 2010-2017 Highsoft AS
 * Author: Oystein Moseng
 *
 * License: www.highcharts.com/license
 */
'use strict';
(function (factory) {
	if (typeof module === 'object' && module.exports) {
		module.exports = factory;
	} else if (typeof define === 'function' && define.amd) {
		define(function () {
			return factory;
		});
	} else {
		factory(Highcharts);
	}
}(function (Highcharts) {
	(function (H) {
		/**
		 * Accessibility module - internationalization support
		 *
		 * (c) 2010-2018 Highsoft AS
		 * Author: Øystein Moseng
		 *
		 * License: www.highcharts.com/license
		 */


		var each = H.each,
		    pick = H.pick;

		/**
		 * String trim that works for IE6-8 as well.
		 * @param  {string} str The input string
		 * @return {string} The trimmed string
		 */
		function stringTrim(str) {
		    return str.trim && str.trim() || str.replace(/^\s+|\s+$/g, '');
		}

		/**
		 * i18n utility function. Format a single array or plural statement in a format
		 * string. If the statement is not an array or plural statement, returns the
		 * statement within brackets. Invalid array statements return an empty string.
		 */
		function formatExtendedStatement(statement, ctx) {
		    var eachStart = statement.indexOf('#each('),
		        pluralStart = statement.indexOf('#plural('),
		        indexStart = statement.indexOf('['),
		        indexEnd = statement.indexOf(']'),
		        arr,
		        result;

		    // Dealing with an each-function?
		    if (eachStart > -1) {
		        var eachEnd = statement.slice(eachStart).indexOf(')') + eachStart,
		            preEach = statement.substring(0, eachStart),
		            postEach = statement.substring(eachEnd + 1),
		            eachStatement = statement.substring(eachStart + 6, eachEnd),
		            eachArguments = eachStatement.split(','),
		            lenArg = Number(eachArguments[1]),
		            len;
		        result = '';
		        arr = ctx[eachArguments[0]];
		        if (arr) {
		            lenArg = isNaN(lenArg) ? arr.length : lenArg;
		            len = lenArg < 0 ?
		                arr.length + lenArg :
		                Math.min(lenArg, arr.length); // Overshoot
		            // Run through the array for the specified length
		            for (var i = 0; i < len; ++i) {
		                result += preEach + arr[i] + postEach;
		            }
		        }
		        return result.length ? result : '';
		    }

		    // Dealing with a plural-function?
		    if (pluralStart > -1) {
		        var pluralEnd = statement.slice(pluralStart).indexOf(')') + pluralStart,
		            pluralStatement = statement.substring(pluralStart + 8, pluralEnd),
		            pluralArguments = pluralStatement.split(','),
		            num = Number(ctx[pluralArguments[0]]);
		        switch (num) {
		            case 0:
		                result = pick(pluralArguments[4], pluralArguments[1]);
		                break;
		            case 1:
		                result = pick(pluralArguments[2], pluralArguments[1]);
		                break;
		            case 2:
		                result = pick(pluralArguments[3], pluralArguments[1]);
		                break;
		            default:
		                result = pluralArguments[1];
		        }
		        return result ? stringTrim(result) : '';
		    }

		    // Array index
		    if (indexStart > -1) {
		        var arrayName = statement.substring(0, indexStart),
		            ix = Number(statement.substring(indexStart + 1, indexEnd)),
		            val;
		        arr = ctx[arrayName];
		        if (!isNaN(ix) && arr) {
		            if (ix < 0) {
		                val = arr[arr.length + ix];
		                // Handle negative overshoot
		                if (val === undefined) {
		                    val = arr[0];
		                }
		            } else {
		                val = arr[ix];
		                // Handle positive overshoot
		                if (val === undefined) {
		                    val = arr[arr.length - 1];
		                }
		            }
		        }
		        return val !== undefined ? val : '';
		    }

		    // Standard substitution, delegate to H.format or similar
		    return '{' + statement + '}';
		}


		/**
		 * i18n formatting function. Extends H.format() functionality by also handling
		 * arrays and plural conditionals. Arrays can be indexed as follows:
		 *
		 *  Format: 'This is the first index: {myArray[0]}. The last: {myArray[-1]}.'
		 *  Context: { myArray: [0, 1, 2, 3, 4, 5] }
		 *  Result: 'This is the first index: 0. The last: 5.'
		 *
		 * They can also be iterated using the #each() function. This will repeat the
		 * contents of the bracket expression for each element. Example:
		 *
		 *  Format: 'List contains: {#each(myArray)cm }'
		 *  Context: { myArray: [0, 1, 2] }
		 *  Result: 'List contains: 0cm 1cm 2cm '
		 *
		 * The #each() function optionally takes a length parameter. If positive, this
		 * parameter specifies the max number of elements to iterate through. If
		 * negative, the function will subtract the number from the length of the array.
		 * Use this to stop iterating before the array ends. Example:
		 *
		 *  Format: 'List contains: {#each(myArray, -1) }and {myArray[-1]}.'
		 *  Context: { myArray: [0, 1, 2, 3] }
		 *  Result: 'List contains: 0, 1, 2, and 3.'
		 *
		 * Use the #plural() function to pick a string depending on whether or not a
		 * context object is 1. Arguments are #plural(obj, plural, singular). Example:
		 *
		 *  Format: 'Has {numPoints} {#plural(numPoints, points, point}.'
		 *  Context: { numPoints: 5 }
		 *  Result: 'Has 5 points.'
		 *
		 * Optionally there are additional parameters for dual and none:
		 *  #plural(obj,plural,singular,dual,none)
		 * Example:
		 *
		 *  Format: 'Has {#plural(numPoints, many points, one point, two points, none}.'
		 *  Context: { numPoints: 2 }
		 *  Result: 'Has two points.'
		 *
		 * The dual or none parameters will take precedence if they are supplied.
		 *
		 * @param   {string} formatString The string to format.
		 * @param   {object} context Context to apply to the format string.
		 * @param   {Time} time A `Time` instance for date formatting, passed on to
		 *                 H.format().
		 * @return  {string} The formatted string.
		 */
		H.i18nFormat = function (formatString, context, time) {
		    var getFirstBracketStatement = function (sourceStr, offset) {
		            var str = sourceStr.slice(offset || 0),
		                startBracket = str.indexOf('{'),
		                endBracket = str.indexOf('}');
		            if (startBracket > -1 && endBracket > startBracket) {
		                return {
		                    statement: str.substring(startBracket + 1, endBracket),
		                    begin: offset + startBracket + 1,
		                    end: offset + endBracket
		                };
		            }
		        },
		        tokens = [],
		        bracketRes,
		        constRes,
		        cursor = 0;

		    // Tokenize format string into bracket statements and constants
		    do {
		        bracketRes = getFirstBracketStatement(formatString, cursor);
		        constRes = formatString.substring(
		            cursor,
		            bracketRes && bracketRes.begin - 1
		        );

		        // If we have constant content before this bracket statement, add it
		        if (constRes.length) {
		            tokens.push({
		                value: constRes,
		                type: 'constant'
		            });
		        }

		        // Add the bracket statement
		        if (bracketRes) {
		            tokens.push({
		                value: bracketRes.statement,
		                type: 'statement'
		            });
		        }

		        cursor = bracketRes && bracketRes.end + 1;
		    } while (bracketRes);

		    // Perform the formatting. The formatArrayStatement function returns the
		    // statement in brackets if it is not an array statement, which means it
		    // gets picked up by H.format below.
		    each(tokens, function (token) {
		        if (token.type === 'statement') {
		            token.value = formatExtendedStatement(token.value, context);
		        }
		    });

		    // Join string back together and pass to H.format to pick up non-array
		    // statements.
		    return H.format(H.reduce(tokens, function (acc, cur) {
		        return acc + cur.value;
		    }, ''), context, time);
		};


		/**
		 * Apply context to a format string from lang options of the chart.
		 * @param  {string} langKey Key (using dot notation) into lang option structure
		 * @param  {object} context Context to apply to the format string
		 * @return {string} The formatted string
		 */
		H.Chart.prototype.langFormat = function (langKey, context, time) {
		    var keys = langKey.split('.'),
		        formatString = this.options.lang,
		        i = 0;
		    for (; i < keys.length; ++i) {
		        formatString = formatString && formatString[keys[i]];
		    }
		    return typeof formatString === 'string' && H.i18nFormat(
		        formatString, context, time
		    );
		};

		H.setOptions({
		    lang: {
		        /**
		         * Configure the accessibility strings in the chart. Requires the
		         * [accessibility module](//code.highcharts.com/modules/accessibility.
		         * js) to be loaded. For a description of the module and information
		         * on its features, see [Highcharts Accessibility](http://www.highcharts.
		         * com/docs/chart-concepts/accessibility).
		         *
		         * For more dynamic control over the accessibility functionality, see
		         * [accessibility.pointDescriptionFormatter](
		         * accessibility.pointDescriptionFormatter),
		         * [accessibility.seriesDescriptionFormatter](
		         * accessibility.seriesDescriptionFormatter), and
		         * [accessibility.screenReaderSectionFormatter](
		         * accessibility.screenReaderSectionFormatter).
		         *
		         * @since 6.0.6
		         * @type {Object}
		         * @optionparent lang.accessibility
		         */
		        accessibility: {
		            /* eslint-disable max-len */

		            screenReaderRegionLabel: 'Chart screen reader information.',
		            navigationHint: 'Use regions/landmarks to skip ahead to chart {#plural(numSeries, and navigate between data series,)}',
		            defaultChartTitle: 'Chart',
		            longDescriptionHeading: 'Long description.',
		            noDescription: 'No description available.',
		            structureHeading: 'Structure.',
		            viewAsDataTable: 'View as data table.',
		            chartHeading: 'Chart graphic.',
		            chartContainerLabel: 'Interactive chart. {title}. Use up and down arrows to navigate with most screen readers.',
		            rangeSelectorMinInput: 'Select start date.',
		            rangeSelectorMaxInput: 'Select end date.',
		            tableSummary: 'Table representation of chart.',
		            mapZoomIn: 'Zoom chart',
		            mapZoomOut: 'Zoom out chart',
		            rangeSelectorButton: 'Select range {buttonText}',
		            legendItem: 'Toggle visibility of series {itemName}',

		            /**
		             * Title element text for the chart SVG element. Leave this
		             * empty to disable adding the title element. Browsers will display
		             * this content when hovering over elements in the chart. Assistive
		             * technology may use this element to label the chart.
		             *
		             * @since 6.0.8
		             */
		            svgContainerTitle: '{chartTitle}',

		            /**
		             * Descriptions of lesser known series types. The relevant
		             * description is added to the screen reader information region
		             * when these series types are used.
		             *
		             * @since 6.0.6
		             * @type {Object}
		             * @optionparent lang.accessibility.seriesTypeDescriptions
		             */
		            seriesTypeDescriptions: {
		                boxplot: 'Box plot charts are typically used to display ' +
		                    'groups of statistical data. Each data point in the ' +
		                    'chart can have up to 5 values: minimum, lower quartile, ' +
		                    'median, upper quartile, and maximum.',
		                arearange: 'Arearange charts are line charts displaying a ' +
		                    'range between a lower and higher value for each point.',
		                areasplinerange: 'These charts are line charts displaying a ' +
		                    'range between a lower and higher value for each point.',
		                bubble: 'Bubble charts are scatter charts where each data ' +
		                    'point also has a size value.',
		                columnrange: 'Columnrange charts are column charts ' +
		                    'displaying a range between a lower and higher value for ' +
		                    'each point.',
		                errorbar: 'Errorbar series are used to display the ' +
		                    'variability of the data.',
		                funnel: 'Funnel charts are used to display reduction of data ' +
		                    'in stages.',
		                pyramid: 'Pyramid charts consist of a single pyramid with ' +
		                    'item heights corresponding to each point value.',
		                waterfall: 'A waterfall chart is a column chart where each ' +
		                    'column contributes towards a total end value.'
		            },

		            /**
		             * Chart type description strings. This is added to the chart
		             * information region.
		             *
		             * If there is only a single series type used in the chart, we use
		             * the format string for the series type, or default if missing.
		             * There is one format string for cases where there is only a single
		             * series in the chart, and one for multiple series of the same
		             * type.
		             *
		             * @since 6.0.6
		             * @type {Object}
		             * @optionparent lang.accessibility.chartTypes
		             */
		            chartTypes: {
		                emptyChart: 'Empty chart',
		                mapTypeDescription: 'Map of {mapTitle} with {numSeries} data series.',
		                unknownMap: 'Map of unspecified region with {numSeries} data series.',
		                combinationChart: 'Combination chart with {numSeries} data series.',
		                defaultSingle: 'Chart with {numPoints} data {#plural(numPoints, points, point)}.',
		                defaultMultiple: 'Chart with {numSeries} data series.',
		                splineSingle: 'Line chart with {numPoints} data {#plural(numPoints, points, point)}.',
		                splineMultiple: 'Line chart with {numSeries} lines.',
		                lineSingle: 'Line chart with {numPoints} data {#plural(numPoints, points, point)}.',
		                lineMultiple: 'Line chart with {numSeries} lines.',
		                columnSingle: 'Bar chart with {numPoints} {#plural(numPoints, bars, bar)}.',
		                columnMultiple: 'Bar chart with {numSeries} data series.',
		                barSingle: 'Bar chart with {numPoints} {#plural(numPoints, bars, bar)}.',
		                barMultiple: 'Bar chart with {numSeries} data series.',
		                pieSingle: 'Pie chart with {numPoints} {#plural(numPoints, slices, slice)}.',
		                pieMultiple: 'Pie chart with {numSeries} pies.',
		                scatterSingle: 'Scatter chart with {numPoints} {#plural(numPoints, points, point)}.',
		                scatterMultiple: 'Scatter chart with {numSeries} data series.',
		                boxplotSingle: 'Boxplot with {numPoints} {#plural(numPoints, boxes, box)}.',
		                boxplotMultiple: 'Boxplot with {numSeries} data series.',
		                bubbleSingle: 'Bubble chart with {numPoints} {#plural(numPoints, bubbles, bubble)}.',
		                bubbleMultiple: 'Bubble chart with {numSeries} data series.'
		            },

		            /**
		             * Axis description format strings.
		             *
		             * @since 6.0.6
		             * @type {Object}
		             * @optionparent lang.accessibility.axis
		             */
		            axis: {
		                xAxisDescriptionSingular: 'The chart has 1 X axis displaying {names[0]}.',
		                xAxisDescriptionPlural: 'The chart has {numAxes} X axes displaying {#each(names, -1) }and {names[-1]}',
		                yAxisDescriptionSingular: 'The chart has 1 Y axis displaying {names[0]}.',
		                yAxisDescriptionPlural: 'The chart has {numAxes} Y axes displaying {#each(names, -1) }and {names[-1]}'
		            },

		            /**
		             * Exporting menu format strings for accessibility module.
		             *
		             * @since 6.0.6
		             * @type {Object}
		             * @optionparent lang.accessibility.exporting
		             */
		            exporting: {
		                chartMenuLabel: 'Chart export',
		                menuButtonLabel: 'View export menu',
		                exportRegionLabel: 'Chart export menu'
		            },

		            /**
		             * Lang configuration for different series types. For more dynamic
		             * control over the series element descriptions, see
		             * [accessibility.seriesDescriptionFormatter](
		             * accessibility.seriesDescriptionFormatter).
		             *
		             * @since 6.0.6
		             * @type {Object}
		             * @optionparent lang.accessibility.series
		             */
		            series: {
		                /**
		                 * Lang configuration for the series main summary. Each series
		                 * type has two modes:
		                 *     1. This series type is the only series type used in the
		                 *        chart
		                 *    2. This is a combination chart with multiple series types
		                 *
		                 * If a definition does not exist for the specific series type
		                 * and mode, the 'default' lang definitions are used.
		                 *
		                 * @since 6.0.6
		                 * @type {Object}
		                 * @optionparent lang.accessibility.series.summary
		                 */
		                summary: {
		                    default: '{name}, series {ix} of {numSeries} with {numPoints} data {#plural(numPoints, points, point)}.',
		                    defaultCombination: '{name}, series {ix} of {numSeries} with {numPoints} data {#plural(numPoints, points, point)}.',
		                    line: '{name}, line {ix} of {numSeries} with {numPoints} data {#plural(numPoints, points, point)}.',
		                    lineCombination: '{name}, series {ix} of {numSeries}. Line with {numPoints} data {#plural(numPoints, points, point)}.',
		                    spline: '{name}, line {ix} of {numSeries} with {numPoints} data {#plural(numPoints, points, point)}.',
		                    splineCombination: '{name}, series {ix} of {numSeries}. Line with {numPoints} data {#plural(numPoints, points, point)}.',
		                    column: '{name}, bar series {ix} of {numSeries} with {numPoints} {#plural(numPoints, bars, bar)}.',
		                    columnCombination: '{name}, series {ix} of {numSeries}. Bar series with {numPoints} {#plural(numPoints, bars, bar)}.',
		                    bar: '{name}, bar series {ix} of {numSeries} with {numPoints} {#plural(numPoints, bars, bar)}.',
		                    barCombination: '{name}, series {ix} of {numSeries}. Bar series with {numPoints} {#plural(numPoints, bars, bar)}.',
		                    pie: '{name}, pie {ix} of {numSeries} with {numPoints} {#plural(numPoints, slices, slice)}.',
		                    pieCombination: '{name}, series {ix} of {numSeries}. Pie with {numPoints} {#plural(numPoints, slices, slice)}.',
		                    scatter: '{name}, scatter plot {ix} of {numSeries} with {numPoints} {#plural(numPoints, points, point)}.',
		                    scatterCombination: '{name}, series {ix} of {numSeries}, scatter plot with {numPoints} {#plural(numPoints, points, point)}.',
		                    boxplot: '{name}, boxplot {ix} of {numSeries} with {numPoints} {#plural(numPoints, boxes, box)}.',
		                    boxplotCombination: '{name}, series {ix} of {numSeries}. Boxplot with {numPoints} {#plural(numPoints, boxes, box)}.',
		                    bubble: '{name}, bubble series {ix} of {numSeries} with {numPoints} {#plural(numPoints, bubbles, bubble)}.',
		                    bubbleCombination: '{name}, series {ix} of {numSeries}. Bubble series with {numPoints} {#plural(numPoints, bubbles, bubble)}.',
		                    map: '{name}, map {ix} of {numSeries} with {numPoints} {#plural(numPoints, areas, area)}.',
		                    mapCombination: '{name}, series {ix} of {numSeries}. Map with {numPoints} {#plural(numPoints, areas, area)}.',
		                    mapline: '{name}, line {ix} of {numSeries} with {numPoints} data {#plural(numPoints, points, point)}.',
		                    maplineCombination: '{name}, series {ix} of {numSeries}. Line with {numPoints} data {#plural(numPoints, points, point)}.',
		                    mapbubble: '{name}, bubble series {ix} of {numSeries} with {numPoints} {#plural(numPoints, bubbles, bubble)}.',
		                    mapbubbleCombination: '{name}, series {ix} of {numSeries}. Bubble series with {numPoints} {#plural(numPoints, bubbles, bubble)}.'
		                },
		                /* eslint-enable max-len */

		                /**
		                 * User supplied description text. This is added after the main
		                 * summary if present.
		                 *
		                 * @type {String}
		                 * @since 6.0.6
		                 */
		                description: '{description}',

		                /**
		                 * xAxis description for series if there are multiple xAxes in
		                 * the chart.
		                 *
		                 * @type {String}
		                 * @since 6.0.6
		                 */
		                xAxisDescription: 'X axis, {name}',

		                /**
		                 * yAxis description for series if there are multiple yAxes in
		                 * the chart.
		                 *
		                 * @type {String}
		                 * @since 6.0.6
		                 */
		                yAxisDescription: 'Y axis, {name}'
		            }
		        }
		    }
		});

	}(Highcharts));
	(function (H) {
		/**
		 * Accessibility module - Screen Reader support
		 *
		 * (c) 2010-2017 Highsoft AS
		 * Author: Oystein Moseng
		 *
		 * License: www.highcharts.com/license
		 */


		var win = H.win,
		    doc = win.document,
		    each = H.each,
		    map = H.map,
		    erase = H.erase,
		    addEvent = H.addEvent,
		    merge = H.merge,
		    // CSS style to hide element from visual users while still exposing it to
		    // screen readers
		    hiddenStyle = {
		        position: 'absolute',
		        left: '-9999px',
		        top: 'auto',
		        width: '1px',
		        height: '1px',
		        overflow: 'hidden'
		    };

		// If a point has one of the special keys defined, we expose all keys to the
		// screen reader.
		H.Series.prototype.commonKeys = ['name', 'id', 'category', 'x', 'value', 'y'];
		H.Series.prototype.specialKeys = [
		    'z', 'open', 'high', 'q3', 'median', 'q1', 'low', 'close'
		];
		if (H.seriesTypes.pie) {
		    // A pie is always simple. Don't quote me on that.
		    H.seriesTypes.pie.prototype.specialKeys = [];
		}


		/**
		 * HTML encode some characters vulnerable for XSS.
		 * @param  {string} html The input string
		 * @return {string} The excaped string
		 */
		function htmlencode(html) {
		    return html
		        .replace(/&/g, '&amp;')
		        .replace(/</g, '&lt;')
		        .replace(/>/g, '&gt;')
		        .replace(/"/g, '&quot;')
		        .replace(/'/g, '&#x27;')
		        .replace(/\//g, '&#x2F;');
		}


		/**
		 * Strip HTML tags away from a string. Used for aria-label attributes, painting
		 * on a canvas will fail if the text contains tags.
		 * @param  {String} s The input string
		 * @return {String}   The filtered string
		 */
		function stripTags(s) {
		    return typeof s === 'string' ? s.replace(/<\/?[^>]+(>|$)/g, '') : s;
		}


		/**
		 * Accessibility options
		 */
		H.setOptions({

		    /**
		     * Options for configuring accessibility for the chart. Requires the
		     * [accessibility module](//code.highcharts.com/modules/accessibility.
		     * js) to be loaded. For a description of the module and information
		     * on its features, see [Highcharts Accessibility](http://www.highcharts.
		     * com/docs/chart-concepts/accessibility).
		     *
		     * @since 5.0.0
		     * @type {Object}
		     * @optionparent accessibility
		     */
		    accessibility: {

		        /**
		         * Whether or not to add series descriptions to charts with a single
		         * series.
		         *
		         * @type {Boolean}
		         * @default false
		         * @since 5.0.0
		         * @apioption accessibility.describeSingleSeries
		         */

		        /**
		         * Function to run upon clicking the "View as Data Table" link in the
		         * screen reader region.
		         *
		         * By default Highcharts will insert and set focus to a data table
		         * representation of the chart.
		         *
		         * @type {Function}
		         * @since 5.0.0
		         * @apioption accessibility.onTableAnchorClick
		         */

		        /**
		         * Date format to use for points on datetime axes when describing them
		         * to screen reader users.
		         *
		         * Defaults to the same format as in tooltip.
		         *
		         * For an overview of the replacement codes, see
		         * [dateFormat](/class-reference/Highcharts#dateFormat).
		         *
		         * @type {String}
		         * @see [pointDateFormatter](#accessibility.pointDateFormatter)
		         * @since 5.0.0
		         * @apioption accessibility.pointDateFormat
		         */

		        /**
		         * Formatter function to determine the date/time format used with
		         * points on datetime axes when describing them to screen reader users.
		         * Receives one argument, `point`, referring to the point to describe.
		         * Should return a date format string compatible with
		         * [dateFormat](/class-reference/Highcharts#dateFormat).
		         *
		         * @type {Function}
		         * @see [pointDateFormat](#accessibility.pointDateFormat)
		         * @since 5.0.0
		         * @apioption accessibility.pointDateFormatter
		         */

		        /**
		         * Formatter function to use instead of the default for point
		         * descriptions.
		         * Receives one argument, `point`, referring to the point to describe.
		         * Should return a String with the description of the point for a screen
		         * reader user.
		         *
		         * @type {Function}
		         * @see [point.description](#series.line.data.description)
		         * @since 5.0.0
		         * @apioption accessibility.pointDescriptionFormatter
		         */

		        /**
		         * Formatter function to use instead of the default for series
		         * descriptions. Receives one argument, `series`, referring to the
		         * series to describe. Should return a String with the description of
		         * the series for a screen reader user.
		         *
		         * @type {Function}
		         * @see [series.description](#plotOptions.series.description)
		         * @since 5.0.0
		         * @apioption accessibility.seriesDescriptionFormatter
		         */

		        /**
		         * Enable accessibility features for the chart.
		         *
		         * @type {Boolean}
		         * @default true
		         * @since 5.0.0
		         */
		        enabled: true,

		        /**
		         * When a series contains more points than this, we no longer expose
		         * information about individual points to screen readers.
		         *
		         * Set to `false` to disable.
		         *
		         * @type {Number|Boolean}
		         * @since 5.0.0
		         */
		        pointDescriptionThreshold: false, // set to false to disable

		        /**
		         * A formatter function to create the HTML contents of the hidden screen
		         * reader information region. Receives one argument, `chart`, referring
		         * to the chart object. Should return a String with the HTML content
		         * of the region.
		         *
		         * The link to view the chart as a data table will be added
		         * automatically after the custom HTML content.
		         *
		         * @type {Function}
		         * @default undefined
		         * @since 5.0.0
		         */
		        screenReaderSectionFormatter: function (chart) {
		            var options = chart.options,
		                chartTypes = chart.types || [],
		                formatContext = {
		                    chart: chart,
		                    numSeries: chart.series && chart.series.length
		                },
		                // Build axis info - but not for pies and maps. Consider not
		                // adding for certain other types as well (funnel, pyramid?)
		                axesDesc = (
		                    chartTypes.length === 1 && chartTypes[0] === 'pie' ||
		                    chartTypes[0] === 'map'
		                ) && {} || chart.getAxesDescription();

		            return '<div>' + chart.langFormat(
		                        'accessibility.navigationHint', formatContext
		                    ) + '</div><h3>' +
		                    (
		                        options.title.text ?
		                            htmlencode(options.title.text) :
		                            chart.langFormat(
		                                'accessibility.defaultChartTitle', formatContext
		                            )
		                    ) +
		                    (
		                        options.subtitle && options.subtitle.text ?
		                            '. ' + htmlencode(options.subtitle.text) :
		                            ''
		                    ) +
		                    '</h3><h4>' + chart.langFormat(
		                        'accessibility.longDescriptionHeading', formatContext
		                    ) + '</h4><div>' +
		                    (
		                        options.chart.description || chart.langFormat(
		                            'accessibility.noDescription', formatContext
		                        )
		                    ) +
		                    '</div><h4>' + chart.langFormat(
		                        'accessibility.structureHeading', formatContext
		                    ) + '</h4><div>' +
		                    (
		                        options.chart.typeDescription ||
		                        chart.getTypeDescription()
		                    ) + '</div>' +
		                    (axesDesc.xAxis ? (
		                        '<div>' + axesDesc.xAxis + '</div>'
		                    ) : '') +
		                    (axesDesc.yAxis ? (
		                        '<div>' + axesDesc.yAxis + '</div>'
		                    ) : '');
		        }
		    }
		});

		/**
		 * A text description of the chart.
		 *
		 * If the Accessibility module is loaded, this is included by default
		 * as a long description of the chart and its contents in the hidden
		 * screen reader information region.
		 *
		 * @type {String}
		 * @see [typeDescription](#chart.typeDescription)
		 * @default undefined
		 * @since 5.0.0
		 * @apioption chart.description
		 */

		 /**
		 * A text description of the chart type.
		 *
		 * If the Accessibility module is loaded, this will be included in the
		 * description of the chart in the screen reader information region.
		 *
		 *
		 * Highcharts will by default attempt to guess the chart type, but for
		 * more complex charts it is recommended to specify this property for
		 * clarity.
		 *
		 * @type {String}
		 * @default undefined
		 * @since 5.0.0
		 * @apioption chart.typeDescription
		 */


		// Utility function. Reverses child nodes of a DOM element
		function reverseChildNodes(node) {
		    var i = node.childNodes.length;
		    while (i--) {
		        node.appendChild(node.childNodes[i]);
		    }
		}


		// Whenever drawing series, put info on DOM elements
		H.addEvent(H.Series, 'afterRender', function () {
		    if (this.chart.options.accessibility.enabled) {
		        this.setA11yDescription();
		    }
		});


		// Put accessible info on series and points of a series
		H.Series.prototype.setA11yDescription = function () {
		    var a11yOptions = this.chart.options.accessibility,
		        firstPointEl = (
		            this.points &&
		            this.points.length &&
		            this.points[0].graphic &&
		            this.points[0].graphic.element
		        ),
		        seriesEl = (
		            firstPointEl &&
		            firstPointEl.parentNode || this.graph &&
		            this.graph.element || this.group &&
		            this.group.element
		        ); // Could be tracker series depending on series type

		    if (seriesEl) {
		        // For some series types the order of elements do not match the order of
		        // points in series. In that case we have to reverse them in order for
		        // AT to read them out in an understandable order
		        if (seriesEl.lastChild === firstPointEl) {
		            reverseChildNodes(seriesEl);
		        }
		        // Make individual point elements accessible if possible. Note: If
		        // markers are disabled there might not be any elements there to make
		        // accessible.
		        if (
		            this.points && (
		                this.points.length < a11yOptions.pointDescriptionThreshold ||
		                a11yOptions.pointDescriptionThreshold === false
		            )
		        ) {
		            each(this.points, function (point) {
		                if (point.graphic) {
		                    point.graphic.element.setAttribute('role', 'img');
		                    point.graphic.element.setAttribute('tabindex', '-1');
		                    point.graphic.element.setAttribute('aria-label', stripTags(
		                        point.series.options.pointDescriptionFormatter &&
		                        point.series.options.pointDescriptionFormatter(point) ||
		                        a11yOptions.pointDescriptionFormatter &&
		                        a11yOptions.pointDescriptionFormatter(point) ||
		                        point.buildPointInfoString()
		                    ));
		                }
		            });
		        }
		        // Make series element accessible
		        if (this.chart.series.length > 1 || a11yOptions.describeSingleSeries) {
		            seriesEl.setAttribute(
		                'role',
		                this.options.exposeElementToA11y ? 'img' : 'region'
		            );
		            seriesEl.setAttribute('tabindex', '-1');
		            seriesEl.setAttribute(
		                'aria-label',
		                stripTags(
		                    a11yOptions.seriesDescriptionFormatter &&
		                    a11yOptions.seriesDescriptionFormatter(this) ||
		                    this.buildSeriesInfoString()
		                )
		            );
		        }
		    }
		};


		// Return string with information about series
		H.Series.prototype.buildSeriesInfoString = function () {
		    var chart = this.chart,
		        desc = this.description || this.options.description,
		        description = desc && chart.langFormat(
		            'accessibility.series.description', {
		                description: desc,
		                series: this
		            }
		        ),
		        xAxisInfo = chart.langFormat(
		            'accessibility.series.xAxisDescription',
		            {
		                name: this.xAxis && this.xAxis.getDescription(),
		                series: this
		            }
		        ),
		        yAxisInfo = chart.langFormat(
		            'accessibility.series.yAxisDescription',
		            {
		                name: this.yAxis && this.yAxis.getDescription(),
		                series: this
		            }
		        ),
		        summaryContext = {
		            name: this.name || '',
		            ix: this.index + 1,
		            numSeries: chart.series.length,
		            numPoints: this.points.length,
		            series: this
		        },
		        combination = chart.types.length === 1 ? '' : 'Combination',
		        summary = chart.langFormat(
		            'accessibility.series.summary.' + this.type + combination,
		            summaryContext
		        ) || chart.langFormat(
		            'accessibility.series.summary.default' + combination,
		            summaryContext
		        );

		    return summary + (description ? ' ' + description : '') + (
		            chart.yAxis.length > 1 && this.yAxis ?
		                ' ' + yAxisInfo : ''
		        ) + (
		            chart.xAxis.length > 1 && this.xAxis ?
		                ' ' + xAxisInfo : ''
		        );
		};


		// Return string with information about point
		H.Point.prototype.buildPointInfoString = function () {
		    var point = this,
		        series = point.series,
		        a11yOptions = series.chart.options.accessibility,
		        infoString = '',
		        dateTimePoint = series.xAxis && series.xAxis.isDatetimeAxis,
		        timeDesc =
		            dateTimePoint &&
		            series.chart.time.dateFormat(
		                a11yOptions.pointDateFormatter &&
		                a11yOptions.pointDateFormatter(point) ||
		                a11yOptions.pointDateFormat ||
		                H.Tooltip.prototype.getXDateFormat.call(
		                    {
		                        getDateFormat: H.Tooltip.prototype.getDateFormat,
		                        chart: series.chart
		                    },
		                    point,
		                    series.chart.options.tooltip,
		                    series.xAxis
		                ),
		                point.x
		            ),
		        hasSpecialKey = H.find(series.specialKeys, function (key) {
		            return point[key] !== undefined;
		        });

		    // If the point has one of the less common properties defined, display all
		    // that are defined
		    if (hasSpecialKey) {
		        if (dateTimePoint) {
		            infoString = timeDesc;
		        }
		        each(series.commonKeys.concat(series.specialKeys), function (key) {
		            if (point[key] !== undefined && !(dateTimePoint && key === 'x')) {
		                infoString += (infoString ? '. ' : '') +
		                    key + ', ' +
		                    point[key];
		            }
		        });
		    } else {
		        // Pick and choose properties for a succint label
		        infoString =
		            (
		                this.name ||
		                timeDesc ||
		                this.category ||
		                this.id ||
		                'x, ' + this.x
		            ) + ', ' +
		            (this.value !== undefined ? this.value : this.y);
		    }

		    return (this.index + 1) + '. ' + infoString + '.' +
		        (this.description ? ' ' + this.description : '');
		};


		// Get descriptive label for axis
		H.Axis.prototype.getDescription = function () {
		    return (
		        this.userOptions && this.userOptions.description ||
		        this.axisTitle && this.axisTitle.textStr ||
		        this.options.id ||
		        this.categories && 'categories' ||
		        this.isDatetimeAxis && 'Time' ||
		        'values'
		    );
		};


		// Whenever adding or removing series, keep track of types present in chart
		addEvent(H.Series, 'afterInit', function () {
		    var chart = this.chart;
		    if (chart.options.accessibility.enabled) {
		        chart.types = chart.types || [];

		        // Add type to list if does not exist
		        if (chart.types.indexOf(this.type) < 0) {
		            chart.types.push(this.type);
		        }
		    }
		});
		addEvent(H.Series, 'remove', function () {
		    var chart = this.chart,
		        removedSeries = this,
		        hasType = false;

		    // Check if any of the other series have the same type as this one.
		    // Otherwise remove it from the list.
		    each(chart.series, function (s) {
		        if (
		            s !== removedSeries &&
		            chart.types.indexOf(removedSeries.type) < 0
		        ) {
		            hasType = true;
		        }
		    });
		    if (!hasType) {
		        erase(chart.types, removedSeries.type);
		    }
		});


		// Return simplified description of chart type. Some types will not be familiar
		// to most screen reader users, but in those cases we try to add a description
		// of the type.
		H.Chart.prototype.getTypeDescription = function () {
		    var firstType = this.types && this.types[0],
		        firstSeries = this.series && this.series[0] || {},
		        mapTitle = firstSeries.mapTitle,
		        typeDesc = this.langFormat(
		            'accessibility.seriesTypeDescriptions.' + firstType,
		            { chart: this }
		        ),
		        formatContext = {
		            numSeries: this.series.length,
		            numPoints: firstSeries.points && firstSeries.points.length,
		            chart: this,
		            mapTitle: mapTitle
		        },
		        multi = this.series && this.series.length === 1 ? 'Single' : 'Multiple';

		    if (!firstType) {
		        return this.langFormat(
		            'accessibility.chartTypes.emptyChart', formatContext
		        );
		    } else if (firstType === 'map') {
		        return mapTitle ?
		            this.langFormat(
		                'accessibility.chartTypes.mapTypeDescription',
		                formatContext
		            ) :
		            this.langFormat(
		                'accessibility.chartTypes.unknownMap',
		                formatContext
		            );
		    } else if (this.types.length > 1) {
		        return this.langFormat(
		            'accessibility.chartTypes.combinationChart', formatContext
		        );
		    }

		    return (
		        this.langFormat(
		            'accessibility.chartTypes.' + firstType + multi,
		            formatContext
		        ) ||
		        this.langFormat(
		            'accessibility.chartTypes.default' + multi,
		            formatContext
		        )
		    ) +
		    (typeDesc ? ' ' + typeDesc : '');
		};


		// Return object with text description of each of the chart's axes
		H.Chart.prototype.getAxesDescription = function () {
		    var numXAxes = this.xAxis.length,
		        numYAxes = this.yAxis.length,
		        desc = {};

		    if (numXAxes) {
		        desc.xAxis = this.langFormat(
		            'accessibility.axis.xAxisDescription' + (
		                numXAxes > 1 ? 'Plural' : 'Singular'
		            ),
		            {
		                chart: this,
		                names: map(this.xAxis, function (axis) {
		                    return axis.getDescription();
		                }),
		                numAxes: numXAxes
		            }
		        );
		    }

		    if (numYAxes) {
		        desc.yAxis = this.langFormat(
		            'accessibility.axis.yAxisDescription' + (
		                numYAxes > 1 ? 'Plural' : 'Singular'
		            ),
		            {
		                chart: this,
		                names: map(this.yAxis, function (axis) {
		                    return axis.getDescription();
		                }),
		                numAxes: numYAxes
		            }
		        );
		    }

		    return desc;
		};


		// Set a11y attribs on exporting menu
		H.Chart.prototype.addAccessibleContextMenuAttribs = function () {
		    var exportList = this.exportDivElements;
		    if (exportList) {
		        // Set tabindex on the menu items to allow focusing by script
		        // Set role to give screen readers a chance to pick up the contents
		        each(exportList, function (item) {
		            if (item.tagName === 'DIV' &&
		                !(item.children && item.children.length)) {
		                item.setAttribute('role', 'menuitem');
		                item.setAttribute('tabindex', -1);
		            }
		        });
		        // Set accessibility properties on parent div
		        exportList[0].parentNode.setAttribute('role', 'menu');
		        exportList[0].parentNode.setAttribute('aria-label',
		            this.langFormat(
		                'accessibility.exporting.chartMenuLabel', { chart: this }
		            )
		        );
		    }
		};


		// Add screen reader region to chart.
		// tableId is the HTML id of the table to focus when clicking the table anchor
		// in the screen reader region.
		H.Chart.prototype.addScreenReaderRegion = function (id, tableId) {
		    var chart = this,
		        hiddenSection = chart.screenReaderRegion = doc.createElement('div'),
		        tableShortcut = doc.createElement('h4'),
		        tableShortcutAnchor = doc.createElement('a'),
		        chartHeading = doc.createElement('h4');

		    hiddenSection.setAttribute('id', id);
		    hiddenSection.setAttribute('role', 'region');
		    hiddenSection.setAttribute(
		        'aria-label',
		        chart.langFormat(
		            'accessibility.screenReaderRegionLabel', { chart: this }
		        )
		    );

		    hiddenSection.innerHTML = chart.options.accessibility
		        .screenReaderSectionFormatter(chart);

		    // Add shortcut to data table if export-data is loaded
		    if (chart.getCSV) {
		        tableShortcutAnchor.innerHTML = chart.langFormat(
		            'accessibility.viewAsDataTable', { chart: chart }
		        );
		        tableShortcutAnchor.href = '#' + tableId;
		        // Make this unreachable by user tabbing
		        tableShortcutAnchor.setAttribute('tabindex', '-1');
		        tableShortcutAnchor.onclick =
		            chart.options.accessibility.onTableAnchorClick || function () {
		                chart.viewData();
		                doc.getElementById(tableId).focus();
		            };
		        tableShortcut.appendChild(tableShortcutAnchor);
		        hiddenSection.appendChild(tableShortcut);
		    }

		    // Note: JAWS seems to refuse to read aria-label on the container, so add an
		    // h4 element as title for the chart.
		    chartHeading.innerHTML = chart.langFormat(
		        'accessibility.chartHeading', { chart: chart }
		    );
		    chart.renderTo.insertBefore(chartHeading, chart.renderTo.firstChild);
		    chart.renderTo.insertBefore(hiddenSection, chart.renderTo.firstChild);

		    // Hide the section and the chart heading
		    merge(true, chartHeading.style, hiddenStyle);
		    merge(true, hiddenSection.style, hiddenStyle);
		};


		// Make chart container accessible, and wrap table functionality
		H.Chart.prototype.callbacks.push(function (chart) {
		    var options = chart.options,
		        a11yOptions = options.accessibility;

		    if (!a11yOptions.enabled) {
		        return;
		    }

		    var titleElement,
		        descElement = chart.container.getElementsByTagName('desc')[0],
		        textElements = chart.container.getElementsByTagName('text'),
		        titleId = 'highcharts-title-' + chart.index,
		        tableId = 'highcharts-data-table-' + chart.index,
		        hiddenSectionId = 'highcharts-information-region-' + chart.index,
		        chartTitle = options.title.text || chart.langFormat(
		            'accessibility.defaultChartTitle', { chart: chart }
		        ),
		        svgContainerTitle = stripTags(chart.langFormat(
		            'accessibility.svgContainerTitle', {
		                chartTitle: chartTitle
		            }
		        ));

		    // Add SVG title tag if it is set
		    if (svgContainerTitle.length) {
		        titleElement = doc.createElementNS(
		                'http://www.w3.org/2000/svg',
		                'title'
		            );
		        titleElement.textContent = svgContainerTitle;
		        titleElement.id = titleId;
		        descElement.parentNode.insertBefore(titleElement, descElement);
		    }

		    chart.renderTo.setAttribute('role', 'region');
		    chart.renderTo.setAttribute(
		        'aria-label',
		        chart.langFormat(
		            'accessibility.chartContainerLabel',
		            {
		                title: stripTags(chartTitle),
		                chart: chart
		            }
		        )
		    );

		    // Set screen reader properties on export menu
		    if (
		        chart.exportSVGElements &&
		        chart.exportSVGElements[0] &&
		        chart.exportSVGElements[0].element
		    ) {
		        // Set event handler on button
		        var button = chart.exportSVGElements[0].element,
		            oldExportCallback = button.onclick;
		        button.onclick = function () {
		            oldExportCallback.apply(
		                this,
		                Array.prototype.slice.call(arguments)
		            );
		            chart.addAccessibleContextMenuAttribs();
		            chart.highlightExportItem(0);
		        };

		        // Set props on button
		        button.setAttribute('role', 'button');
		        button.setAttribute(
		            'aria-label',
		            chart.langFormat(
		                'accessibility.exporting.menuButtonLabel', { chart: chart }
		            )
		        );

		        // Set props on group
		        chart.exportingGroup.element.setAttribute('role', 'region');
		        chart.exportingGroup.element.setAttribute('aria-label',
		            chart.langFormat(
		                'accessibility.exporting.exportRegionLabel', { chart: chart }
		            )
		        );
		    }

		    // Set screen reader properties on input boxes for range selector. We need
		    // to do this regardless of whether or not these are visible, as they are
		    // by default part of the page's tabindex unless we set them to -1.
		    if (chart.rangeSelector) {
		        each(['minInput', 'maxInput'], function (key, i) {
		            if (chart.rangeSelector[key]) {
		                chart.rangeSelector[key].setAttribute('tabindex', '-1');
		                chart.rangeSelector[key].setAttribute('role', 'textbox');
		                chart.rangeSelector[key].setAttribute(
		                    'aria-label',
		                    chart.langFormat(
		                        'accessibility.rangeSelector' +
		                            (i ? 'MaxInput' : 'MinInput'), { chart: chart }
		                    )
		                );
		            }
		        });
		    }

		    // Hide text elements from screen readers
		    each(textElements, function (el) {
		        el.setAttribute('aria-hidden', 'true');
		    });

		    // Add top-secret screen reader region
		    chart.addScreenReaderRegion(hiddenSectionId, tableId);

		    // Add ID and summary attr to table HTML
		    H.wrap(chart, 'getTable', function (proceed) {
		        return proceed.apply(this, Array.prototype.slice.call(arguments, 1))
		            .replace(
		                '<table>',
		                '<table id="' + tableId + '" summary="' + chart.langFormat(
		                    'accessibility.tableSummary', { chart: chart }
		                ) + '">'
		            );
		    });
		});

	}(Highcharts));
	(function (H) {
		/**
		 * Accessibility module - Keyboard navigation
		 *
		 * (c) 2010-2017 Highsoft AS
		 * Author: Oystein Moseng
		 *
		 * License: www.highcharts.com/license
		 */


		var win = H.win,
		    doc = win.document,
		    each = H.each,
		    addEvent = H.addEvent,
		    fireEvent = H.fireEvent,
		    merge = H.merge,
		    pick = H.pick,
		    hasSVGFocusSupport;

		// Add focus border functionality to SVGElements.
		// Draws a new rect on top of element around its bounding box.
		H.extend(H.SVGElement.prototype, {
		    addFocusBorder: function (margin, style) {
		        // Allow updating by just adding new border
		        if (this.focusBorder) {
		            this.removeFocusBorder();
		        }
		        // Add the border rect
		        var bb = this.getBBox(),
		            pad = pick(margin, 3);
		        this.focusBorder = this.renderer.rect(
		            bb.x - pad,
		            bb.y - pad,
		            bb.width + 2 * pad,
		            bb.height + 2 * pad,
		            style && style.borderRadius
		        )
		        .addClass('highcharts-focus-border')
        
		        .attr({
		            zIndex: 99
		        })
		        .add(this.parentGroup);
		    },

		    removeFocusBorder: function () {
		        if (this.focusBorder) {
		            this.focusBorder.destroy();
		            delete this.focusBorder;
		        }
		    }
		});


		// Set for which series types it makes sense to move to the closest point with
		// up/down arrows, and which series types should just move to next series.
		H.Series.prototype.keyboardMoveVertical = true;
		each(['column', 'pie'], function (type) {
		    if (H.seriesTypes[type]) {
		        H.seriesTypes[type].prototype.keyboardMoveVertical = false;
		    }
		});


		/**
		 * Strip HTML tags away from a string. Used for aria-label attributes, painting
		 * on a canvas will fail if the text contains tags.
		 * @param  {String} s The input string
		 * @return {String}   The filtered string
		 */
		function stripTags(s) {
		    return typeof s === 'string' ? s.replace(/<\/?[^>]+(>|$)/g, '') : s;
		}


		/**
		 * Get the index of a point in a series. This is needed when using e.g. data
		 * grouping.
		 *
		 * @param {Point} point The point to find index of.
		 * @return {number} The index in the series.points array of the point.
		 */
		function getPointIndex(point) {
		    var index = point.index,
		        points = point.series.points,
		        i = points.length;
		    if (points[index] !== point) {
		        while (i--) {
		            if (points[i] === point) {
		                return i;
		            }
		        }
		    } else {
		        return index;
		    }
		}


		/**
		 * Set default keyboard navigation options
		 */
		H.setOptions({
		    accessibility: {

		        /**
		         * Options for keyboard navigation.
		         *
		         * @type      {Object}
		         * @since     5.0.0
		         * @apioption accessibility.keyboardNavigation
		         */
		        keyboardNavigation: {

		            /**
		             * Enable keyboard navigation for the chart.
		             *
		             * @type      {Boolean}
		             * @default   true
		             * @since     5.0.0
		             * @apioption accessibility.keyboardNavigation.enabled
		             */
		            enabled: true,


		            /**
		             * Options for the focus border drawn around elements while
		             * navigating through them.
		             *
		             * @type      {Object}
		             * @sample    highcharts/accessibility/custom-focus
		             *            Custom focus ring
		             * @since     6.0.3
		             * @apioption accessibility.keyboardNavigation.focusBorder
		             */
		            focusBorder: {
		                /**
		                 * Enable/disable focus border for chart.
		                 *
		                 * @type      {Boolean}
		                 * @default   true
		                 * @since     6.0.3
		                 * @apioption accessibility.keyboardNavigation.focusBorder.enabled
		                 */
		                enabled: true,

		                /**
		                 * Hide the browser's default focus indicator.
		                 *
		                 * @type      {Boolean}
		                 * @default   true
		                 * @since     6.0.4
		                 * @apioption accessibility.keyboardNavigation.focusBorder.hideBrowserFocusOutline
		                 */
		                hideBrowserFocusOutline: true,

		                /**
		                 * Style options for the focus border drawn around elements
		                 * while navigating through them. Note that some browsers in
		                 * addition draw their own borders for focused elements. These
		                 * automatic borders can not be styled by Highcharts.
		                 *
		                 * In styled mode, the border is given the
		                 * `.highcharts-focus-border` class.
		                 *
		                 * @type      {Object}
		                 * @since     6.0.3
		                 * @apioption accessibility.keyboardNavigation.focusBorder.style
		                 */
		                style: {
		                    /**
		                     * Color of the focus border.
		                     *
		                     * @type      {Color}
		                     * @default   #000000
		                     * @since     6.0.3
		                     * @apioption accessibility.keyboardNavigation.focusBorder.style.color
		                    */
		                    color: '#335cad',
		                    /**
		                     * Line width of the focus border.
		                     *
		                     * @type      {Number}
		                     * @default   2
		                     * @since     6.0.3
		                     * @apioption accessibility.keyboardNavigation.focusBorder.style.lineWidth
		                    */
		                    lineWidth: 2,
		                    /**
		                     * Border radius of the focus border.
		                     *
		                     * @type      {Number}
		                     * @default   3
		                     * @since     6.0.3
		                     * @apioption accessibility.keyboardNavigation.focusBorder.style.borderRadius
		                    */
		                    borderRadius: 3
		                },

		                /**
		                 * Focus border margin around the elements.
		                 *
		                 * @type      {Number}
		                 * @default   2
		                 * @since     6.0.3
		                 * @apioption accessibility.keyboardNavigation.focusBorder.margin
		                 */
		                margin: 2
		            },

		            /**
		             * Set the keyboard navigation mode for the chart. Can be "normal"
		             * or "serialize". In normal mode, left/right arrow keys move
		             * between points in a series, while up/down arrow keys move between
		             * series. Up/down navigation acts intelligently to figure out which
		             * series makes sense to move to from any given point.
		             *
		             * In "serialize" mode, points are instead navigated as a single
		             * list. Left/right behaves as in "normal" mode. Up/down arrow keys
		             * will behave like left/right. This is useful for unifying
		             * navigation behavior with/without screen readers enabled.
		             *
		             * @type      {String}
		             * @validvalue ["normal", "serialize"]
		             * @default   normal
		             * @since     6.0.4
		             * @apioption accessibility.keyboardNavigation.mode
		             */

		            /**
		             * Skip null points when navigating through points with the
		             * keyboard.
		             *
		             * @type      {Boolean}
		             * @default   true
		             * @since     5.0.0
		             * @apioption accessibility.keyboardNavigation.skipNullPoints
		             */
		            skipNullPoints: true
		        }
		    }
		});

		/**
		 * Keyboard navigation for the legend. Requires the Accessibility module.
		 * @since 5.0.14
		 * @apioption legend.keyboardNavigation
		 */

		/**
		 * Enable/disable keyboard navigation for the legend. Requires the Accessibility
		 * module.
		 *
		 * @type {Boolean}
		 * @see [accessibility.keyboardNavigation](
		 *      #accessibility.keyboardNavigation.enabled)
		 * @default true
		 * @since 5.0.13
		 * @apioption legend.keyboardNavigation.enabled
		 */


		// Abstraction layer for keyboard navigation. Keep a map of keyCodes to
		// handler functions, and a next/prev move handler for tab order. The
		// module's keyCode handlers determine when to move to another module.
		// Validate holds a function to determine if there are prerequisites for
		// this module to run that are not met. Init holds a function to run once
		// before any keyCodes are interpreted. Terminate holds a function to run
		// once before moving to next/prev module.
		// The chart object keeps track of a list of KeyboardNavigationModules.
		function KeyboardNavigationModule(chart, options) {
		    this.chart = chart;
		    this.id = options.id;
		    this.keyCodeMap = options.keyCodeMap;
		    this.validate = options.validate;
		    this.init = options.init;
		    this.terminate = options.terminate;
		}
		KeyboardNavigationModule.prototype = {
		    // Find handler function(s) for key code in the keyCodeMap and run it.
		    run: function (e) {
		        var navModule = this,
		            keyCode = e.which || e.keyCode,
		            found = false,
		            handled = false;
		        each(this.keyCodeMap, function (codeSet) {
		            if (codeSet[0].indexOf(keyCode) > -1) {
		                found = true;
		                handled = codeSet[1].call(navModule, keyCode, e) === false ?
		                    // If explicitly returning false, we haven't handled it
		                    false :
		                    true;
		            }
		        });
		        // Default tab handler, move to next/prev module
		        if (!found && keyCode === 9) {
		            handled = this.move(e.shiftKey ? -1 : 1);
		        }
		        return handled;
		    },

		    // Move to next/prev valid module, or undefined if none, and init
		    // it. Returns true on success and false if there is no valid module
		    // to move to.
		    move: function (direction) {
		        var chart = this.chart;
		        if (this.terminate) {
		            this.terminate(direction);
		        }
		        chart.keyboardNavigationModuleIndex += direction;
		        var newModule = chart.keyboardNavigationModules[
		            chart.keyboardNavigationModuleIndex
		        ];

		        // Remove existing focus border if any
		        if (chart.focusElement) {
		            chart.focusElement.removeFocusBorder();
		        }

		        // Verify new module
		        if (newModule) {
		            if (newModule.validate && !newModule.validate()) {
		                return this.move(direction); // Invalid module, recurse
		            }
		            if (newModule.init) {
		                newModule.init(direction); // Valid module, init it
		                return true;
		            }
		        }
		        // No module
		        chart.keyboardNavigationModuleIndex = 0; // Reset counter

		        // Set focus to chart or exit anchor depending on direction
		        if (direction > 0) {
		            this.chart.exiting = true;
		            this.chart.tabExitAnchor.focus();
		        } else {
		            this.chart.renderTo.focus();
		        }

		        return false;
		    }
		};


		// Utility function to attempt to fake a click event on an element
		function fakeClickEvent(element) {
		    var fakeEvent;
		    if (element && element.onclick && doc.createEvent) {
		        fakeEvent = doc.createEvent('Events');
		        fakeEvent.initEvent('click', true, false);
		        element.onclick(fakeEvent);
		    }
		}


		// Determine if a series should be skipped
		function isSkipSeries(series) {
		    var a11yOptions = series.chart.options.accessibility;
		    return series.options.skipKeyboardNavigation ||
		        series.options.enableMouseTracking === false || // #8440
		        !series.visible ||
		        // Skip all points in a series where pointDescriptionThreshold is
		        // reached
		        (a11yOptions.pointDescriptionThreshold &&
		        a11yOptions.pointDescriptionThreshold <= series.points.length);
		}


		// Determine if a point should be skipped
		function isSkipPoint(point) {
		    var a11yOptions = point.series.chart.options.accessibility;
		    return point.isNull && a11yOptions.keyboardNavigation.skipNullPoints ||
		        point.visible === false ||
		        isSkipSeries(point.series);
		}


		// Get the point in a series that is closest (in distance) to a reference point
		// Optionally supply weight factors for x and y directions
		function getClosestPoint(point, series, xWeight, yWeight) {
		    var minDistance = Infinity,
		        dPoint,
		        minIx,
		        distance,
		        i = series.points.length;
		    if (point.plotX === undefined || point.plotY === undefined) {
		        return;
		    }
		    while (i--) {
		        dPoint = series.points[i];
		        if (dPoint.plotX === undefined || dPoint.plotY === undefined) {
		            continue;
		        }
		        distance = (point.plotX - dPoint.plotX) *
		                (point.plotX - dPoint.plotX) * (xWeight || 1) +
		                (point.plotY - dPoint.plotY) *
		                (point.plotY - dPoint.plotY) * (yWeight || 1);
		        if (distance < minDistance) {
		            minDistance = distance;
		            minIx = i;
		        }
		    }
		    return minIx !== undefined && series.points[minIx];
		}


		// Pan along axis in a direction (1 or -1), optionally with a defined
		// granularity (number of steps it takes to walk across current view)
		H.Axis.prototype.panStep = function (direction, granularity) {
		    var gran = granularity || 3,
		        extremes = this.getExtremes(),
		        step = (extremes.max - extremes.min) / gran * direction,
		        newMax = extremes.max + step,
		        newMin = extremes.min + step,
		        size = newMax - newMin;
		    if (direction < 0 && newMin < extremes.dataMin) {
		        newMin = extremes.dataMin;
		        newMax = newMin + size;
		    } else if (direction > 0 && newMax > extremes.dataMax) {
		        newMax = extremes.dataMax;
		        newMin = newMax - size;
		    }
		    this.setExtremes(newMin, newMax);
		};


		// Set chart's focus to an SVGElement. Calls focus() on it, and draws the focus
		// border. If the focusElement argument is supplied, it draws the border around
		// svgElement and sets the focus to focusElement.
		H.Chart.prototype.setFocusToElement = function (svgElement, focusElement) {
		    var focusBorderOptions = this.options.accessibility
		                .keyboardNavigation.focusBorder,
		        browserFocusElement = focusElement || svgElement;
		    // Set browser focus if possible
		    if (
		        browserFocusElement.element &&
		        browserFocusElement.element.focus
		    ) {
		        browserFocusElement.element.focus();
		        // Hide default focus ring
		        if (focusBorderOptions.hideBrowserFocusOutline) {
		            browserFocusElement.css({ outline: 'none' });
		        }
		    }
		    if (focusBorderOptions.enabled) {
		        // Remove old focus border
		        if (this.focusElement) {
		            this.focusElement.removeFocusBorder();
		        }
		        // Draw focus border (since some browsers don't do it automatically)
		        svgElement.addFocusBorder(focusBorderOptions.margin, {
		            stroke: focusBorderOptions.style.color,
		            strokeWidth: focusBorderOptions.style.lineWidth,
		            borderRadius: focusBorderOptions.style.borderRadius
		        });
		        this.focusElement = svgElement;
		    }
		};


		// Highlight a point (show tooltip and display hover state). Returns the
		// highlighted point.
		H.Point.prototype.highlight = function () {
		    var chart = this.series.chart;
		    if (!this.isNull) {
		        this.onMouseOver(); // Show the hover marker and tooltip
		    } else {
		        if (chart.tooltip) {
		            chart.tooltip.hide(0);
		        }
		        // Don't call blur on the element, as it messes up the chart div's focus
		    }

		    // We focus only after calling onMouseOver because the state change can
		    // change z-index and mess up the element.
		    if (this.graphic) {
		        chart.setFocusToElement(this.graphic);
		    }

		    chart.highlightedPoint = this;
		    return this;
		};


		// Function to highlight next/previous point in chart
		// Returns highlighted point on success, false on failure (no adjacent point to
		// highlight in chosen direction)
		H.Chart.prototype.highlightAdjacentPoint = function (next) {
		    var chart = this,
		        series = chart.series,
		        curPoint = chart.highlightedPoint,
		        curPointIndex = curPoint && getPointIndex(curPoint) || 0,
		        curPoints = curPoint && curPoint.series.points,
		        lastSeries = chart.series && chart.series[chart.series.length - 1],
		        lastPoint = lastSeries && lastSeries.points &&
		                    lastSeries.points[lastSeries.points.length - 1],
		        newSeries,
		        newPoint;

		    // If no points, return false
		    if (!series[0] || !series[0].points) {
		        return false;
		    }

		    if (!curPoint) {
		        // No point is highlighted yet. Try first/last point depending on move
		        // direction
		        newPoint = next ? series[0].points[0] : lastPoint;
		    } else {
		        // We have a highlighted point.
		        // Grab next/prev point & series
		        newSeries = series[curPoint.series.index + (next ? 1 : -1)];
		        newPoint = curPoints[curPointIndex + (next ? 1 : -1)];
		        if (!newPoint && newSeries) {
		            // Done with this series, try next one
		            newPoint = newSeries.points[next ? 0 : newSeries.points.length - 1];
		        }

		        // If there is no adjacent point, we return false
		        if (!newPoint) {
		            return false;
		        }
		    }

		    // Recursively skip points
		    if (isSkipPoint(newPoint)) {
		        // If we skip this whole series, move to the end of the series before we
		        // recurse, just to optimize
		        newSeries = newPoint.series;
		        if (isSkipSeries(newSeries)) {
		            chart.highlightedPoint = next ?
		                newSeries.points[newSeries.points.length - 1] :
		                newSeries.points[0];
		        } else {
		            // Otherwise, just move one point
		            chart.highlightedPoint = newPoint;
		        }
		        // Retry
		        return chart.highlightAdjacentPoint(next);
		    }

		    // There is an adjacent point, highlight it
		    return newPoint.highlight();
		};


		// Highlight first valid point in a series. Returns the point if successfully
		// highlighted, otherwise false. If there is a highlighted point in the series,
		// use that as starting point.
		H.Series.prototype.highlightFirstValidPoint = function () {
		    var curPoint = this.chart.highlightedPoint,
		        start = (curPoint && curPoint.series) === this ?
		            getPointIndex(curPoint) :
		            0,
		        points = this.points;

		    if (points) {
		        for (var i = start, len = points.length; i < len; ++i) {
		            if (!isSkipPoint(points[i])) {
		                return points[i].highlight();
		            }
		        }
		        for (var j = start; j >= 0; --j) {
		            if (!isSkipPoint(points[j])) {
		                return points[j].highlight();
		            }
		        }
		    }
		    return false;
		};


		// Highlight next/previous series in chart. Returns false if no adjacent series
		// in the direction, otherwise returns new highlighted point.
		H.Chart.prototype.highlightAdjacentSeries = function (down) {
		    var chart = this,
		        newSeries,
		        newPoint,
		        adjacentNewPoint,
		        curPoint = chart.highlightedPoint,
		        lastSeries = chart.series && chart.series[chart.series.length - 1],
		        lastPoint = lastSeries && lastSeries.points &&
		                    lastSeries.points[lastSeries.points.length - 1];

		    // If no point is highlighted, highlight the first/last point
		    if (!chart.highlightedPoint) {
		        newSeries = down ? (chart.series && chart.series[0]) : lastSeries;
		        newPoint = down ?
		            (newSeries && newSeries.points && newSeries.points[0]) : lastPoint;
		        return newPoint ? newPoint.highlight() : false;
		    }

		    newSeries = chart.series[curPoint.series.index + (down ? -1 : 1)];

		    if (!newSeries) {
		        return false;
		    }

		    // We have a new series in this direction, find the right point
		    // Weigh xDistance as counting much higher than Y distance
		    newPoint = getClosestPoint(curPoint, newSeries, 4);

		    if (!newPoint) {
		        return false;
		    }

		    // New series and point exists, but we might want to skip it
		    if (isSkipSeries(newSeries)) {
		        // Skip the series
		        newPoint.highlight();
		        adjacentNewPoint = chart.highlightAdjacentSeries(down); // Try recurse
		        if (!adjacentNewPoint) {
		            // Recurse failed
		            curPoint.highlight();
		            return false;
		        }
		        // Recurse succeeded
		        return adjacentNewPoint;
		    }

		    // Highlight the new point or any first valid point back or forwards from it
		    newPoint.highlight();
		    return newPoint.series.highlightFirstValidPoint();
		};


		// Highlight the closest point vertically
		H.Chart.prototype.highlightAdjacentPointVertical = function (down) {
		    var curPoint = this.highlightedPoint,
		        minDistance = Infinity,
		        bestPoint;

		    if (curPoint.plotX === undefined || curPoint.plotY === undefined) {
		        return false;
		    }
		    each(this.series, function (series) {
		        if (isSkipSeries(series)) {
		            return;
		        }
		        each(series.points, function (point) {
		            if (point.plotY === undefined || point.plotX === undefined ||
		                point === curPoint) {
		                return;
		            }
		            var yDistance = point.plotY - curPoint.plotY,
		                width = Math.abs(point.plotX - curPoint.plotX),
		                distance = Math.abs(yDistance) * Math.abs(yDistance) +
		                    width * width * 4; // Weigh horizontal distance highly

		            // Reverse distance number if axis is reversed
		            if (series.yAxis.reversed) {
		                yDistance *= -1;
		            }

		            if (
		                yDistance < 0 && down || yDistance > 0 && !down || // Wrong dir
		                distance < 5 || // Points in same spot => infinite loop
		                isSkipPoint(point)
		            ) {
		                return;
		            }

		            if (distance < minDistance) {
		                minDistance = distance;
		                bestPoint = point;
		            }
		        });
		    });

		    return bestPoint ? bestPoint.highlight() : false;
		};


		// Show the export menu and focus the first item (if exists)
		H.Chart.prototype.showExportMenu = function () {
		    if (this.exportSVGElements && this.exportSVGElements[0]) {
		        this.exportSVGElements[0].element.onclick();
		        this.highlightExportItem(0);
		    }
		};


		// Hide export menu
		H.Chart.prototype.hideExportMenu = function () {
		    var chart = this,
		        exportList = chart.exportDivElements;
		    if (exportList && chart.exportContextMenu) {
		        // Reset hover states etc.
		        each(exportList, function (el) {
		            if (el.className === 'highcharts-menu-item' && el.onmouseout) {
		                el.onmouseout();
		            }
		        });
		        chart.highlightedExportItem = 0;
		        // Hide the menu div
		        chart.exportContextMenu.hideMenu();
		        // Make sure the chart has focus and can capture keyboard events
		        chart.container.focus();
		    }
		};


		// Highlight export menu item by index
		H.Chart.prototype.highlightExportItem = function (ix) {
		    var listItem = this.exportDivElements && this.exportDivElements[ix],
		        curHighlighted =
		            this.exportDivElements &&
		            this.exportDivElements[this.highlightedExportItem];

		    if (
		        listItem &&
		        listItem.tagName === 'DIV' &&
		        !(listItem.children && listItem.children.length)
		    ) {
		        if (listItem.focus && hasSVGFocusSupport) {
		            // Only focus if we can set focus back to the elements after
		            // destroying the menu (#7422)
		            listItem.focus();
		        }
		        if (curHighlighted && curHighlighted.onmouseout) {
		            curHighlighted.onmouseout();
		        }
		        if (listItem.onmouseover) {
		            listItem.onmouseover();
		        }
		        this.highlightedExportItem = ix;
		        return true;
		    }
		};


		// Try to highlight the last valid export menu item
		H.Chart.prototype.highlightLastExportItem = function () {
		    var chart = this,
		        i;
		    if (chart.exportDivElements) {
		        i = chart.exportDivElements.length;
		        while (i--) {
		            if (chart.highlightExportItem(i)) {
		                break;
		            }
		        }
		    }
		};


		// Highlight range selector button by index
		H.Chart.prototype.highlightRangeSelectorButton = function (ix) {
		    var buttons = this.rangeSelector.buttons;
		    // Deselect old
		    if (buttons[this.highlightedRangeSelectorItemIx]) {
		        buttons[this.highlightedRangeSelectorItemIx].setState(
		            this.oldRangeSelectorItemState || 0
		        );
		    }
		    // Select new
		    this.highlightedRangeSelectorItemIx = ix;
		    if (buttons[ix]) {
		        this.setFocusToElement(buttons[ix].box, buttons[ix]);
		        this.oldRangeSelectorItemState = buttons[ix].state;
		        buttons[ix].setState(2);
		        return true;
		    }
		    return false;
		};


		// Highlight legend item by index
		H.Chart.prototype.highlightLegendItem = function (ix) {
		    var items = this.legend.allItems,
		        oldIx = this.highlightedLegendItemIx;
		    if (items[ix]) {
		        if (items[oldIx]) {
		            fireEvent(
		                items[oldIx].legendGroup.element,
		                'mouseout'
		            );
		        }
		        // Scroll if we have to
		        if (items[ix].pageIx !== undefined &&
		            items[ix].pageIx + 1 !== this.legend.currentPage) {
		            this.legend.scroll(1 + items[ix].pageIx - this.legend.currentPage);
		        }
		        // Focus
		        this.highlightedLegendItemIx = ix;
		        this.setFocusToElement(items[ix].legendItem, items[ix].legendGroup);
		        fireEvent(items[ix].legendGroup.element, 'mouseover');
		        return true;
		    }
		    return false;
		};


		// Add keyboard navigation handling modules to chart
		H.Chart.prototype.addKeyboardNavigationModules = function () {
		    var chart = this;

		    function navModuleFactory(id, keyMap, options) {
		        return new KeyboardNavigationModule(chart, merge({
		            keyCodeMap: keyMap
		        }, { id: id }, options));
		    }

		    // List of the different keyboard handling modes we use depending on where
		    // we are in the chart. Each mode has a set of handling functions mapped to
		    // key codes. Each mode determines when to move to the next/prev mode.
		    chart.keyboardNavigationModules = [
		        // Entry point catching the first tab, allowing users to tab into points
		        // more intuitively.
		        navModuleFactory('entry', []),

		        // Points
		        navModuleFactory('points', [
		            // Left/Right
		            [[37, 39], function (keyCode) {
		                var right = keyCode === 39;
		                if (!chart.highlightAdjacentPoint(right)) {
		                    // Failed to highlight next, wrap to last/first
		                    return this.init(right ? 1 : -1);
		                }
		                return true;
		            }],
		            // Up/Down
		            [[38, 40], function (keyCode) {
		                var down = keyCode !== 38,
		                    navOptions = chart.options.accessibility.keyboardNavigation;
		                if (navOptions.mode && navOptions.mode === 'serialize') {
		                    // Act like left/right
		                    if (!chart.highlightAdjacentPoint(down)) {
		                        return this.init(down ? 1 : -1);
		                    }
		                    return true;
		                }
		                // Normal mode, move between series
		                var highlightMethod = chart.highlightedPoint &&
		                        chart.highlightedPoint.series.keyboardMoveVertical ?
		                        'highlightAdjacentPointVertical' :
		                        'highlightAdjacentSeries';
		                chart[highlightMethod](down);
		                return true;
		            }],
		            // Enter/Spacebar
		            [[13, 32], function () {
		                if (chart.highlightedPoint) {
		                    chart.highlightedPoint.firePointEvent('click');
		                }
		            }]
		        ], {
		            // Always start highlighting from scratch when entering this module
		            init: function (dir) {
		                var numSeries = chart.series.length,
		                    i = dir > 0 ? 0 : numSeries,
		                    res;
		                if (dir > 0) {
		                    delete chart.highlightedPoint;
		                    // Find first valid point to highlight
		                    while (i < numSeries) {
		                        res = chart.series[i].highlightFirstValidPoint();
		                        if (res) {
		                            return res;
		                        }
		                        ++i;
		                    }
		                } else {
		                    // Find last valid point to highlight
		                    while (i--) {
		                        chart.highlightedPoint = chart.series[i].points[
		                            chart.series[i].points.length - 1
		                        ];
		                        // Highlight first valid point in the series will also
		                        // look backwards. It always starts from currently
		                        // highlighted point.
		                        res = chart.series[i].highlightFirstValidPoint();
		                        if (res) {
		                            return res;
		                        }
		                    }
		                }
		            },
		            // If leaving points, don't show tooltip anymore
		            terminate: function () {
		                if (chart.tooltip) {
		                    chart.tooltip.hide(0);
		                }
		                delete chart.highlightedPoint;
		            }
		        }),

		        // Exporting
		        navModuleFactory('exporting', [
		            // Left/Up
		            [[37, 38], function () {
		                var i = chart.highlightedExportItem || 0,
		                    reachedEnd = true;
		                // Try to highlight prev item in list. Highlighting e.g.
		                // separators will fail.
		                while (i--) {
		                    if (chart.highlightExportItem(i)) {
		                        reachedEnd = false;
		                        break;
		                    }
		                }
		                if (reachedEnd) {
		                    chart.highlightLastExportItem();
		                    return true;
		                }
		            }],
		            // Right/Down
		            [[39, 40], function () {
		                var highlightedExportItem = chart.highlightedExportItem || 0,
		                    reachedEnd = true;
		                // Try to highlight next item in list. Highlighting e.g.
		                // separators will fail.
		                for (
		                    var i = highlightedExportItem + 1;
		                    i < chart.exportDivElements.length;
		                    ++i
		                ) {
		                    if (chart.highlightExportItem(i)) {
		                        reachedEnd = false;
		                        break;
		                    }
		                }
		                if (reachedEnd) {
		                    chart.highlightExportItem(0);
		                    return true;
		                }
		            }],
		            // Enter/Spacebar
		            [[13, 32], function () {
		                fakeClickEvent(
		                    chart.exportDivElements[chart.highlightedExportItem]
		                );
		            }]
		        ], {
		            // Only run exporting navigation if exporting support exists and is
		            // enabled on chart
		            validate: function () {
		                return (
		                    chart.exportChart &&
		                    !(
		                        chart.options.exporting &&
		                        chart.options.exporting.enabled === false
		                    )
		                );
		            },
		            // Show export menu
		            init: function (direction) {
		                chart.highlightedPoint = null;
		                chart.showExportMenu();
		                // If coming back to export menu from other module, try to
		                // highlight last item in menu
		                if (direction < 0) {
		                    chart.highlightLastExportItem();
		                }
		            },
		            // Hide the menu
		            terminate: function () {
		                chart.hideExportMenu();
		            }
		        }),

		        // Map zoom
		        navModuleFactory('mapZoom', [
		            // Up/down/left/right
		            [[38, 40, 37, 39], function (keyCode) {
		                chart[keyCode === 38 || keyCode === 40 ? 'yAxis' : 'xAxis'][0]
		                    .panStep(keyCode < 39 ? -1 : 1);
		            }],

		            // Tabs
		            [[9], function (keyCode, e) {
		                var button;
		                // Deselect old
		                chart.mapNavButtons[chart.focusedMapNavButtonIx].setState(0);
		                if (
		                    e.shiftKey && !chart.focusedMapNavButtonIx ||
		                    !e.shiftKey && chart.focusedMapNavButtonIx
		                ) { // trying to go somewhere we can't?
		                    chart.mapZoom(); // Reset zoom
		                    // Nowhere to go, go to prev/next module
		                    return this.move(e.shiftKey ? -1 : 1);
		                }
		                chart.focusedMapNavButtonIx += e.shiftKey ? -1 : 1;
		                button = chart.mapNavButtons[chart.focusedMapNavButtonIx];
		                chart.setFocusToElement(button.box, button);
		                button.setState(2);
		            }],

		            // Enter/Spacebar
		            [[13, 32], function () {
		                fakeClickEvent(
		                    chart.mapNavButtons[chart.focusedMapNavButtonIx].element
		                );
		            }]
		        ], {
		            // Only run this module if we have map zoom on the chart
		            validate: function () {
		                return (
		                    chart.mapZoom &&
		                    chart.mapNavButtons &&
		                    chart.mapNavButtons.length === 2
		                );
		            },

		            // Make zoom buttons do their magic
		            init: function (direction) {
		                var zoomIn = chart.mapNavButtons[0],
		                    zoomOut = chart.mapNavButtons[1],
		                    initialButton = direction > 0 ? zoomIn : zoomOut;

		                each(chart.mapNavButtons, function (button, i) {
		                    button.element.setAttribute('tabindex', -1);
		                    button.element.setAttribute('role', 'button');
		                    button.element.setAttribute(
		                        'aria-label',
		                        chart.langFormat(
		                            'accessibility.mapZoom' + (i ? 'Out' : 'In'),
		                            { chart: chart }
		                        )
		                    );
		                });

		                chart.setFocusToElement(initialButton.box, initialButton);
		                initialButton.setState(2);
		                chart.focusedMapNavButtonIx = direction > 0 ? 0 : 1;
		            }
		        }),

		        // Highstock range selector (minus input boxes)
		        navModuleFactory('rangeSelector', [
		            // Left/Right/Up/Down
		            [[37, 39, 38, 40], function (keyCode) {
		                var direction = (keyCode === 37 || keyCode === 38) ? -1 : 1;
		                // Try to highlight next/prev button
		                if (
		                    !chart.highlightRangeSelectorButton(
		                        chart.highlightedRangeSelectorItemIx + direction
		                    )
		                ) {
		                    return this.move(direction);
		                }
		            }],
		            // Enter/Spacebar
		            [[13, 32], function () {
		                // Don't allow click if button used to be disabled
		                if (chart.oldRangeSelectorItemState !== 3) {
		                    fakeClickEvent(
		                        chart.rangeSelector.buttons[
		                            chart.highlightedRangeSelectorItemIx
		                        ].element
		                    );
		                }
		            }]
		        ], {
		            // Only run this module if we have range selector
		            validate: function () {
		                return (
		                    chart.rangeSelector &&
		                    chart.rangeSelector.buttons &&
		                    chart.rangeSelector.buttons.length
		                );
		            },

		            // Make elements focusable and accessible
		            init: function (direction) {
		                each(chart.rangeSelector.buttons, function (button) {
		                    button.element.setAttribute('tabindex', '-1');
		                    button.element.setAttribute('role', 'button');
		                    button.element.setAttribute(
		                        'aria-label',
		                        chart.langFormat(
		                            'accessibility.rangeSelectorButton',
		                            {
		                                chart: chart,
		                                buttonText: button.text && button.text.textStr
		                            }
		                        )
		                    );
		                });
		                // Focus first/last button
		                chart.highlightRangeSelectorButton(
		                    direction > 0 ? 0 : chart.rangeSelector.buttons.length - 1
		                );
		            }
		        }),

		        // Highstock range selector, input boxes
		        navModuleFactory('rangeSelectorInput', [
		            // Tab/Up/Down
		            [[9, 38, 40], function (keyCode, e) {
		                var direction =
		                    (keyCode === 9 && e.shiftKey || keyCode === 38) ? -1 : 1,

		                    newIx = chart.highlightedInputRangeIx =
		                        chart.highlightedInputRangeIx + direction;

		                // Try to highlight next/prev item in list.
		                if (newIx > 1 || newIx < 0) { // Out of range
		                    return this.move(direction);
		                }
		                chart.rangeSelector[newIx ? 'maxInput' : 'minInput'].focus();
		            }]
		        ], {
		            // Only run if we have range selector with input boxes
		            validate: function () {
		                var inputVisible = (
		                    chart.rangeSelector &&
		                    chart.rangeSelector.inputGroup &&
		                    chart.rangeSelector.inputGroup.element
		                        .getAttribute('visibility') !== 'hidden'
		                );
		                return (
		                    inputVisible &&
		                    chart.options.rangeSelector.inputEnabled !== false &&
		                    chart.rangeSelector.minInput &&
		                    chart.rangeSelector.maxInput
		                );
		            },

		            // Highlight first/last input box
		            init: function (direction) {
		                chart.highlightedInputRangeIx = direction > 0 ? 0 : 1;
		                chart.rangeSelector[
		                    chart.highlightedInputRangeIx ? 'maxInput' : 'minInput'
		                ].focus();
		            }
		        }),

		        // Legend navigation
		        navModuleFactory('legend', [
		            // Left/Right/Up/Down
		            [[37, 39, 38, 40], function (keyCode) {
		                var direction = (keyCode === 37 || keyCode === 38) ? -1 : 1;
		                // Try to highlight next/prev legend item
		                if (!chart.highlightLegendItem(
		                    chart.highlightedLegendItemIx + direction
		                ) && chart.legend.allItems.length > 1) {
		                    // Wrap around if more than 1 item
		                    this.init(direction);
		                }
		            }],
		            // Enter/Spacebar
		            [[13, 32], function () {
		                var legendElement = chart.legend.allItems[
		                        chart.highlightedLegendItemIx
		                    ].legendItem.element;
		                fakeClickEvent(
		                     !chart.legend.options.useHTML ? // #8561
		                        legendElement.parentNode : legendElement
		                );
		            }]
		        ], {
		            // Only run this module if we have at least one legend - wait for
		            // it - item. Don't run if the legend is populated by a colorAxis.
		            // Don't run if legend navigation is disabled.
		            validate: function () {
		                return chart.legend && chart.legend.allItems &&
		                    chart.legend.display &&
		                    !(chart.colorAxis && chart.colorAxis.length) &&
		                    (chart.options.legend &&
		                    chart.options.legend.keyboardNavigation &&
		                    chart.options.legend.keyboardNavigation.enabled) !== false;
		            },

		            // Make elements focusable and accessible
		            init: function (direction) {
		                each(chart.legend.allItems, function (item) {
		                    item.legendGroup.element.setAttribute('tabindex', '-1');
		                    item.legendGroup.element.setAttribute('role', 'button');
		                    item.legendGroup.element.setAttribute(
		                        'aria-label',
		                        chart.langFormat(
		                            'accessibility.legendItem',
		                            {
		                                chart: chart,
		                                itemName: stripTags(item.name)
		                            }
		                        )
		                    );
		                });
		                // Focus first/last item
		                chart.highlightLegendItem(
		                    direction > 0 ? 0 : chart.legend.allItems.length - 1
		                );
		            }
		        })
		    ];
		};


		// Add exit anchor to the chart
		// We use this to move focus out of chart whenever we want, by setting focus
		// to this div and not preventing the default tab action.
		// We also use this when users come back into the chart by tabbing back, in
		// order to navigate from the end of the chart.
		// Function returns the unbind function for the exit anchor's event handler.
		H.Chart.prototype.addExitAnchor = function () {
		    var chart = this;
		    chart.tabExitAnchor = doc.createElement('div');
		    chart.tabExitAnchor.setAttribute('tabindex', '0');

		    // Hide exit anchor
		    merge(true, chart.tabExitAnchor.style, {
		        position: 'absolute',
		        left: '-9999px',
		        top: 'auto',
		        width: '1px',
		        height: '1px',
		        overflow: 'hidden'
		    });

		    chart.renderTo.appendChild(chart.tabExitAnchor);
		    return addEvent(chart.tabExitAnchor, 'focus',
		        function (ev) {
		            var e = ev || win.event,
		                curModule;

		            // If focusing and we are exiting, do nothing once.
		            if (!chart.exiting) {

		                // Not exiting, means we are coming in backwards
		                chart.renderTo.focus();
		                e.preventDefault();

		                // Move to last valid keyboard nav module
		                // Note the we don't run it, just set the index
		                chart.keyboardNavigationModuleIndex =
		                    chart.keyboardNavigationModules.length - 1;
		                curModule = chart.keyboardNavigationModules[
		                    chart.keyboardNavigationModuleIndex
		                ];

		                // Validate the module
		                if (curModule.validate && !curModule.validate()) {
		                    // Invalid.
		                    // Move inits next valid module in direction
		                    curModule.move(-1);
		                } else {
		                    // We have a valid module, init it
		                    curModule.init(-1);
		                }

		            } else {
		                // Don't skip the next focus, we only skip once.
		                chart.exiting = false;
		            }
		        }
		    );
		};


		// Clear the chart and reset the navigation state
		H.Chart.prototype.resetKeyboardNavigation = function () {
		    var chart = this,
		        curMod = (
		            chart.keyboardNavigationModules &&
		            chart.keyboardNavigationModules[
		                chart.keyboardNavigationModuleIndex || 0
		            ]
		        );
		    if (curMod && curMod.terminate) {
		        curMod.terminate();
		    }
		    if (chart.focusElement) {
		        chart.focusElement.removeFocusBorder();
		    }
		    chart.keyboardNavigationModuleIndex = 0;
		    chart.keyboardReset = true;
		};


		/**
		 * On destroy, we need to clean up the focus border and the state
		 */
		H.addEvent(H.Series, 'destroy', function () {
		    var chart = this.chart;
		    if (chart.highlightedPoint && chart.highlightedPoint.series === this) {
		        delete chart.highlightedPoint;
		        if (chart.focusElement) {
		            chart.focusElement.removeFocusBorder();
		        }
		    }
		});


		// Add keyboard navigation events on chart load
		H.Chart.prototype.callbacks.push(function (chart) {
		    var a11yOptions = chart.options.accessibility;
		    if (a11yOptions.enabled && a11yOptions.keyboardNavigation.enabled) {

		        // Test if we have focus support for SVG elements
		        hasSVGFocusSupport = !!chart.renderTo
		                                .getElementsByTagName('g')[0].focus;

		        // Init nav modules. We start at the first module, and as the user
		        // navigates through the chart the index will increase to use different
		        // handler modules.
		        chart.addKeyboardNavigationModules();
		        chart.keyboardNavigationModuleIndex = 0;

		        // Make chart container reachable by tab
		        if (
		            chart.container.hasAttribute &&
		            !chart.container.hasAttribute('tabIndex')
		        ) {
		            chart.container.setAttribute('tabindex', '0');
		        }

		        // Add tab exit anchor
		        if (!chart.tabExitAnchor) {
		            chart.unbindExitAnchorFocus = chart.addExitAnchor();
		        }

		        // Handle keyboard events by routing them to active keyboard nav module
		        chart.unbindKeydownHandler = addEvent(chart.renderTo, 'keydown',
		            function (ev) {
		                var e = ev || win.event,
		                    curNavModule = chart.keyboardNavigationModules[
		                        chart.keyboardNavigationModuleIndex
		                    ];
		                chart.keyboardReset = false;
		                // If there is a nav module for the current index, run it.
		                // Otherwise, we are outside of the chart in some direction.
		                if (curNavModule) {
		                    if (curNavModule.run(e)) {
		                        // Successfully handled this key event, stop default
		                        e.preventDefault();
		                    }
		                }
		            });

		        // Reset chart navigation state if we click outside the chart and it's
		        // not already reset
		        chart.unbindBlurHandler = addEvent(doc, 'mouseup', function () {
		            if (
		                !chart.keyboardReset &&
		                !(chart.pointer && chart.pointer.chartPosition)
		            ) {
		                chart.resetKeyboardNavigation();
		            }
		        });

		        // Add cleanup handlers
		        addEvent(chart, 'destroy', function () {
		            chart.resetKeyboardNavigation();
		            if (chart.unbindExitAnchorFocus && chart.tabExitAnchor) {
		                chart.unbindExitAnchorFocus();
		            }
		            if (chart.unbindKeydownHandler && chart.renderTo) {
		                chart.unbindKeydownHandler();
		            }
		            if (chart.unbindBlurHandler) {
		                chart.unbindBlurHandler();
		            }
		        });
		    }
		});

	}(Highcharts));
	return (function () {


	}());
}));