# Gulf of Alaska 1200 Year Surface Air Temperature Reconstruction #----------------------------------------------------------------------- # World Data Center for Paleoclimatology, Boulder # and # NOAA Paleoclimatology Program #----------------------------------------------------------------------- # NOTE: Please cite Publication, and Online_Resource and date accessed when using these data. # If there is no publication information, please cite Investigators, Title, and Online_Resource and date accessed. # # # Online_Resource: http://hurricane.ncdc.noaa.gov/pls/paleox/f?p=519:1:::::P1_STUDY_ID:16015 # # Original_Source_URL: ftp://ftp.ncdc.noaa.gov/pub/data/paleo/treering/reconstructions/gulf_of_alaska/goa2014temperature.txt # # Description/Documentation lines begin with # # Data lines have no # # # Archive: Climate Reconstructions #-------------------- # Contribution_Date # Date: 2014-02-05 #-------------------- # Title # Study_Name: Gulf of Alaska 1200 Year Surface Air Temperature Reconstruction #-------------------- # Investigators # Investigators: Wiles, G.C.; D'Arrigo, R.D.; Barclay, D.; Wilson, R.S.; Jarvis, S.K.; Vargo, L.; Frank, D. #-------------------- # Description_and_Notes # Description: Gulf of Alaska February-August temperature reconstruction for the past 1200 years, based on living and subfossil mountain hemlock ring widths. #-------------------- # Publication # Authors: Gregory C. Wiles, Rosanne D. D'Arrigo, David Barclay, Rob S. Wilson, Stephanie K. Jarvis, Lauren Vargo, and David Frank # Published_Date_or_Year: 2014-02-01 # Published_Title: Surface air temperature variability reconstructed with tree rings for the Gulf of Alaska over the past 1200 years # Journal_Name: The Holocene # Volume: 24 # Edition: # Issue: 2 # Pages: 198-208 # DOI: 10.1177/0959683613516815 # Online_Resource: http://hol.sagepub.com/content/24/2/198.abstract # Full_Citation: # Abstract: A 1200-year-long tree-ring width record from living and subfossil mountain hemlock wood is used to reconstruct February through August temperatures for the Gulf of Alaska, providing a record of past climate variability for the Northeast Pacific sector that captures interannual to centennial timescales. The moderate elevation at the tree-ring sites has allowed these trees to retain their temperature signal without evidence of the so-called divergence effect, or underestimation of tree-ring inferred temperature trends, which is observed at many northern latitude forest locations. This 'divergence-free' reconstruction reveals centennial trends that include a warm interval centered on ad 950 for coastal Alaska that occurs around the time of the 'Medieval Warm Period', a warming that is only rivaled by recent decades. Spectral analysis of this reconstruction supports the centennial pacing identified as a 170-220-year cadence consistent with solar variability. On the decadal to bidecadal scale, the reconstruction reveals ~10- and 18-year cycles, which have been observed elsewhere in climate records for western North America and are linked to solar and lunar tidal forcing, respectively. Temperature minima that occur at ad 969-970 and 1698-1700 correspond with the timing of major volcanic events. This tree-ring reconstruction supports centennial modes of solar forcing as a driver of surface air temperatures in the Gulf of Alaska, with lunar tidal, solar variability, internal variability, and volcanism, impacting climate on annual to decadal timescales. #------------------ # Funding_Agency # Funding_Agency_Name: US National Science Foundation # Grant: ATM-0902799, AGS-1202218, AGS-1159430 #------------------ # Site_Information # Site_Name: Gulf of Alaska # Location: Ocean>Pacific Ocean>North Pacific Ocean>Gulf Of Alaska # Country: # Northernmost_Latitude: 61.00 # Southernmost_Latitude: 57.00 # Easternmost_Longitude: -136.00 # Westernmost_Longitude: -145.00 # Elevation: m #------------------ # Data_Collection # Collection_Name: GOA2014temperature # Earliest_Year: 800 # Most_Recent_Year: 2010 # Time_Unit: AD # Core_Length: m # Notes: #------------------ # Chronology: # # # # # #---------------- # Variables # # Data variables follow (have no #) # Data line variables format: Variables list, one per line, shortname-tab-longname-tab-longname components (9 components: what, material, error, units, seasonality, archive, detail, method, C or N for Character or Numeric data) # ## age_AD age, , , AD, , , , ,N ## temp-FMAMJJA Surface Air Temperature, , , deg C, February-August, , , ,N #---------------- # Data: # Data lines follow (have no #) # Data line format - tab-delimited text, variable short name as header # Missing Values: age_AD temp-FMAMJJA 800 7.6850 801 7.4270 802 7.0620 803 7.1330 804 7.1530 805 7.6530 806 7.8720 807 7.9760 808 8.4350 809 8.0360 810 7.6850 811 8.2980 812 7.3580 813 8.0610 814 7.3110 815 7.5320 816 7.1490 817 7.5910 818 7.5160 819 8.1610 820 7.6690 821 7.6460 822 8.8610 823 7.4840 824 6.7560 825 6.8390 826 6.9120 827 6.3410 828 6.8040 829 7.2130 830 6.7980 831 7.5340 832 7.6340 833 8.7900 834 8.0700 835 6.8930 836 6.7610 837 6.8860 838 6.5400 839 6.6360 840 7.0550 841 7.5230 842 8.0610 843 7.7690 844 7.8420 845 7.1940 846 7.6280 847 7.4610 848 8.2250 849 7.0390 850 7.4880 851 6.6740 852 6.8890 853 6.3210 854 6.3830 855 6.9000 856 6.2000 857 7.6940 858 7.8100 859 7.9330 860 7.7640 861 7.6960 862 7.3380 863 6.8270 864 6.1360 865 6.5030 866 6.2940 867 6.4970 868 6.8590 869 6.6720 870 7.2330 871 7.5640 872 7.8150 873 8.1980 874 8.1340 875 7.8030 876 8.0790 877 7.5590 878 7.5660 879 6.8750 880 7.3900 881 8.0110 882 8.6040 883 7.9510 884 7.3860 885 7.9990 886 8.0270 887 6.7680 888 6.5190 889 6.9460 890 6.7700 891 7.2290 892 8.1730 893 8.5260 894 8.8910 895 8.7200 896 7.3790 897 6.7700 898 6.8450 899 7.1120 900 6.9180 901 7.0280 902 7.1710 903 6.7470 904 7.2010 905 7.3490 906 7.0350 907 7.6370 908 7.0850 909 6.8960 910 7.3560 911 7.8780 912 7.4430 913 7.4130 914 7.8690 915 8.0930 916 7.3400 917 7.6090 918 7.8850 919 7.8670 920 7.2440 921 6.7910 922 6.7430 923 7.3220 924 7.5550 925 7.5770 926 7.6730 927 7.9970 928 7.6390 929 8.4440 930 8.3410 931 8.0540 932 8.3090 933 8.0520 934 7.4150 935 8.0200 936 8.2160 937 8.3410 938 8.0880 939 7.7480 940 6.7700 941 7.4000 942 7.4910 943 8.6470 944 9.0980 945 8.8040 946 8.5760 947 8.1750 948 8.8930 949 9.1170 950 8.0650 951 7.2170 952 6.8270 953 6.8710 954 7.6500 955 8.6290 956 9.4700 957 9.4520 958 8.0310 959 8.1660 960 8.4230 961 8.5970 962 9.1990 963 8.6380 964 9.0690 965 9.2400 966 9.0940 967 9.4220 968 8.9640 969 6.5850 970 5.8440 971 6.0470 972 6.6470 973 7.1530 974 8.2040 975 7.5870 976 7.3310 977 8.0360 978 7.7160 979 8.3600 980 7.6480 981 7.1710 982 6.6040 983 7.0260 984 6.9940 985 7.1940 986 8.1610 987 7.4930 988 7.9860 989 7.4430 990 7.2400 991 6.9820 992 7.3560 993 7.6980 994 7.6410 995 7.9060 996 7.7760 997 8.1520 998 7.9810 999 7.8970 1000 7.2240 1001 6.7290 1002 7.1330 1003 7.9880 1004 8.0290 1005 7.7100 1006 8.2250 1007 8.1220 1008 8.0130 1009 7.7890 1010 6.2750 1011 6.3830 1012 6.5630 1013 6.6880 1014 7.1490 1015 7.4310 1016 7.6730 1017 7.8620 1018 8.3660 1019 7.1870 1020 6.8130 1021 6.6450 1022 6.9120 1023 7.5410 1024 6.3960 1025 6.3050 1026 6.4350 1027 6.3920 1028 6.9300 1029 7.7350 1030 8.2660 1031 8.1470 1032 7.5230 1033 7.8970 1034 7.5000 1035 7.2030 1036 7.3840 1037 7.2630 1038 7.6320 1039 7.4130 1040 7.2670 1041 7.1940 1042 7.4040 1043 7.9810 1044 6.5580 1045 6.3780 1046 6.4710 1047 6.8450 1048 6.4940 1049 7.3450 1050 7.1530 1051 6.9870 1052 6.8660 1053 7.5730 1054 7.3220 1055 7.4590 1056 7.5820 1057 7.5930 1058 7.0830 1059 7.1240 1060 7.6690 1061 7.6050 1062 7.4750 1063 7.7140 1064 7.2810 1065 6.7680 1066 6.8750 1067 6.9710 1068 7.0830 1069 7.0760 1070 7.2880 1071 7.1140 1072 7.4020 1073 7.1830 1074 7.1440 1075 7.1240 1076 7.8670 1077 8.4390 1078 7.6750 1079 8.0130 1080 7.2260 1081 7.2810 1082 8.2180 1083 7.6660 1084 8.3690 1085 8.3940 1086 7.9650 1087 7.8080 1088 7.9700 1089 7.9670 1090 7.8100 1091 6.8200 1092 7.0960 1093 7.3900 1094 6.5720 1095 7.4630 1096 7.7620 1097 7.1690 1098 6.9800 1099 6.6130 1100 6.8430 1101 6.7220 1102 6.8660 1103 7.6020 1104 8.0930 1105 6.9370 1106 7.5290 1107 7.8530 1108 7.5200 1109 7.7320 1110 7.3950 1111 7.2510 1112 6.9850 1113 7.4450 1114 7.7530 1115 7.1560 1116 7.0120 1117 6.6880 1118 7.1210 1119 6.8430 1120 7.0570 1121 6.6220 1122 6.6860 1123 7.2330 1124 7.4930 1125 6.9250 1126 6.9730 1127 7.0780 1128 7.2130 1129 7.7120 1130 7.3330 1131 7.7120 1132 8.0020 1133 6.6420 1134 6.2430 1135 6.8750 1136 6.2480 1137 6.3230 1138 6.2960 1139 6.3800 1140 6.4940 1141 6.4120 1142 6.8200 1143 7.1670 1144 7.9510 1145 7.4860 1146 7.0890 1147 7.3270 1148 7.0160 1149 6.4690 1150 6.6380 1151 6.5720 1152 6.7220 1153 6.9820 1154 7.2880 1155 7.3680 1156 7.3790 1157 7.3400 1158 7.1330 1159 7.0600 1160 6.7200 1161 7.5480 1162 7.2010 1163 7.5160 1164 7.1850 1165 7.2760 1166 7.4250 1167 7.7670 1168 7.1810 1169 6.3780 1170 6.7610 1171 7.2670 1172 6.6220 1173 6.1590 1174 6.5580 1175 6.5440 1176 6.3670 1177 6.8130 1178 7.3170 1179 7.4700 1180 6.7450 1181 7.5090 1182 6.5150 1183 6.8890 1184 6.7180 1185 7.2420 1186 7.0030 1187 7.2130 1188 6.9780 1189 6.5380 1190 6.1930 1191 6.2270 1192 7.0550 1193 6.9570 1194 7.4520 1195 6.9910 1196 6.7680 1197 7.3310 1198 6.7700 1199 7.0280 1200 7.3080 1201 7.3490 1202 7.2010 1203 6.3620 1204 6.8450 1205 6.7840 1206 6.9250 1207 7.1530 1208 7.6000 1209 7.0420 1210 6.9800 1211 6.7700 1212 5.9560 1213 6.8230 1214 6.7200 1215 6.6880 1216 7.1530 1217 6.8710 1218 7.1440 1219 7.2810 1220 7.7890 1221 7.5960 1222 7.1990 1223 7.2190 1224 7.2290 1225 6.9820 1226 7.5360 1227 6.6880 1228 6.9410 1229 7.2560 1230 7.0780 1231 7.3380 1232 6.8570 1233 6.5920 1234 6.0220 1235 6.5670 1236 6.4810 1237 7.1490 1238 7.2130 1239 7.6070 1240 6.9590 1241 6.4650 1242 6.9750 1243 7.1490 1244 7.3150 1245 7.0280 1246 7.0420 1247 7.2990 1248 7.5870 1249 6.9410 1250 6.8450 1251 6.3160 1252 6.4870 1253 6.8360 1254 7.2420 1255 7.9170 1256 7.1670 1257 8.3890 1258 8.0220 1259 7.7870 1260 7.5750 1261 6.6700 1262 6.2320 1263 6.8550 1264 7.3970 1265 7.5480 1266 7.5980 1267 6.7590 1268 7.2380 1269 7.9700 1270 7.4410 1271 7.4290 1272 7.2290 1273 8.2840 1274 7.2720 1275 7.7230 1276 7.7850 1277 7.5020 1278 6.7950 1279 6.6680 1280 6.6580 1281 7.5270 1282 7.4700 1283 7.3270 1284 7.1990 1285 7.6730 1286 7.1920 1287 7.1400 1288 6.8390 1289 6.9250 1290 7.2220 1291 7.3680 1292 7.3060 1293 7.1990 1294 7.6070 1295 7.5640 1296 7.9420 1297 7.3720 1298 7.3810 1299 6.9590 1300 6.8320 1301 6.9020 1302 6.1800 1303 6.4510 1304 6.7360 1305 7.2190 1306 7.2440 1307 8.1160 1308 6.8840 1309 7.5640 1310 7.3860 1311 7.1210 1312 6.7930 1313 7.2920 1314 7.1370 1315 7.1210 1316 7.4470 1317 8.0330 1318 8.4210 1319 7.8920 1320 8.1130 1321 7.8620 1322 7.9540 1323 7.5930 1324 7.1460 1325 7.3740 1326 7.3680 1327 7.1870 1328 7.6050 1329 7.2860 1330 7.5610 1331 7.8370 1332 7.8920 1333 7.3520 1334 7.6280 1335 7.3770 1336 7.7990 1337 7.9720 1338 7.6890 1339 7.4660 1340 6.9940 1341 7.1350 1342 7.4590 1343 6.9020 1344 6.4690 1345 6.8500 1346 7.1870 1347 6.7910 1348 6.3830 1349 7.3680 1350 6.6080 1351 6.7090 1352 7.4980 1353 7.4380 1354 7.7230 1355 7.1650 1356 7.4310 1357 6.8640 1358 7.2030 1359 7.0670 1360 7.1620 1361 6.6010 1362 6.6880 1363 6.6330 1364 7.2810 1365 7.1530 1366 7.1870 1367 7.7010 1368 7.9100 1369 6.5990 1370 7.6570 1371 6.8590 1372 7.0230 1373 6.7180 1374 7.0550 1375 6.9410 1376 7.0460 1377 6.4780 1378 7.1140 1379 7.4820 1380 7.4040 1381 7.7890 1382 8.1470 1383 7.5430 1384 7.5890 1385 7.9510 1386 8.2390 1387 7.8150 1388 6.7310 1389 6.8860 1390 7.1460 1391 7.6850 1392 7.2830 1393 7.6440 1394 7.4820 1395 6.5280 1396 6.7430 1397 6.5970 1398 6.3960 1399 6.3030 1400 6.0470 1401 6.2960 1402 6.4440 1403 6.1270 1404 6.2590 1405 6.3980 1406 6.6470 1407 6.4100 1408 6.8200 1409 6.5260 1410 6.7270 1411 6.6560 1412 6.6310 1413 6.2570 1414 6.3510 1415 6.2750 1416 6.7720 1417 6.4780 1418 6.5440 1419 7.1300 1420 6.9090 1421 6.9640 1422 6.7150 1423 6.6610 1424 7.0600 1425 6.6770 1426 7.1870 1427 7.4380 1428 7.4290 1429 7.0640 1430 7.0260 1431 7.0960 1432 7.4410 1433 6.5720 1434 6.7660 1435 6.7560 1436 7.1400 1437 6.9780 1438 7.3720 1439 7.2330 1440 6.5240 1441 6.5030 1442 6.5900 1443 6.6490 1444 6.2960 1445 6.4780 1446 6.8770 1447 6.8360 1448 6.4330 1449 6.7720 1450 6.3320 1451 6.5380 1452 6.7410 1453 6.6950 1454 6.1700 1455 6.3210 1456 6.2230 1457 6.4010 1458 6.9410 1459 7.0780 1460 7.4660 1461 7.3580 1462 7.0390 1463 6.5240 1464 6.8070 1465 6.6720 1466 6.0610 1467 6.8430 1468 6.6380 1469 6.3030 1470 6.6130 1471 6.4690 1472 6.3730 1473 6.8820 1474 6.3350 1475 6.4030 1476 6.4080 1477 6.2620 1478 6.7430 1479 6.4030 1480 6.2000 1481 6.4190 1482 7.0760 1483 6.9430 1484 6.5810 1485 7.0670 1486 6.7660 1487 6.5440 1488 7.4110 1489 7.0870 1490 6.9070 1491 6.6540 1492 6.5810 1493 6.4100 1494 6.4300 1495 6.2250 1496 6.7750 1497 6.8390 1498 6.6930 1499 7.0640 1500 7.1530 1501 6.7200 1502 6.6470 1503 6.7410 1504 6.9640 1505 6.4850 1506 6.8090 1507 6.8090 1508 6.5740 1509 6.3120 1510 6.6110 1511 7.1560 1512 7.3650 1513 6.9940 1514 7.4180 1515 6.8000 1516 6.5220 1517 6.9800 1518 6.7680 1519 7.0620 1520 7.0530 1521 6.8090 1522 6.8820 1523 7.5680 1524 7.2860 1525 6.9590 1526 7.2240 1527 6.6970 1528 6.5720 1529 7.1030 1530 7.2830 1531 6.9070 1532 6.4900 1533 6.6580 1534 6.7200 1535 7.3240 1536 7.2380 1537 7.4250 1538 7.1600 1539 7.2310 1540 6.9730 1541 7.0760 1542 6.3890 1543 6.6650 1544 7.1650 1545 7.3490 1546 7.3150 1547 7.3150 1548 7.0940 1549 6.6700 1550 7.0920 1551 7.4110 1552 6.6790 1553 6.9570 1554 7.0320 1555 7.2420 1556 7.3860 1557 6.8020 1558 7.8740 1559 7.7710 1560 7.2310 1561 7.3720 1562 7.3130 1563 7.0370 1564 7.2380 1565 7.5770 1566 7.2310 1567 6.6520 1568 6.6520 1569 6.5740 1570 6.7520 1571 6.5540 1572 6.4260 1573 6.7340 1574 6.6650 1575 6.8710 1576 6.6540 1577 6.6650 1578 7.0280 1579 6.8500 1580 6.6200 1581 6.8610 1582 7.2310 1583 7.3490 1584 7.0030 1585 6.3800 1586 6.9410 1587 6.5850 1588 6.6740 1589 6.5510 1590 6.8750 1591 7.3220 1592 7.1080 1593 6.9620 1594 7.4930 1595 7.1970 1596 6.8160 1597 7.4540 1598 6.7660 1599 6.7220 1600 6.6470 1601 6.4940 1602 6.4830 1603 6.4830 1604 6.4400 1605 6.3530 1606 6.6130 1607 6.9570 1608 7.1690 1609 7.2010 1610 7.3650 1611 7.0850 1612 7.2220 1613 6.6700 1614 6.9340 1615 6.6740 1616 7.1530 1617 7.2810 1618 6.7410 1619 6.9620 1620 6.6080 1621 7.1330 1622 7.0690 1623 6.5280 1624 6.3600 1625 6.5670 1626 6.6900 1627 6.9960 1628 7.0870 1629 6.8290 1630 7.3360 1631 6.9980 1632 7.7370 1633 7.0850 1634 7.5910 1635 7.7640 1636 7.3430 1637 7.1900 1638 7.1740 1639 6.4120 1640 7.0990 1641 6.8390 1642 6.9710 1643 6.8500 1644 6.5240 1645 6.9590 1646 6.7770 1647 7.1600 1648 7.0190 1649 6.9300 1650 7.1650 1651 7.6730 1652 7.0990 1653 6.9070 1654 6.8340 1655 6.7200 1656 6.9410 1657 7.0420 1658 6.5240 1659 6.4620 1660 6.5010 1661 6.4870 1662 6.5470 1663 6.2460 1664 6.2800 1665 6.4690 1666 6.6810 1667 6.9160 1668 6.8340 1669 7.0230 1670 6.9890 1671 7.2190 1672 6.7720 1673 6.7680 1674 6.5400 1675 6.7410 1676 6.3410 1677 5.9170 1678 6.2140 1679 5.6920 1680 5.9420 1681 6.4420 1682 6.8610 1683 7.5870 1684 7.3110 1685 7.3970 1686 7.3200 1687 7.4410 1688 7.2510 1689 7.3490 1690 6.9730 1691 6.8570 1692 7.3170 1693 7.3220 1694 7.6050 1695 7.6550 1696 6.7020 1697 6.1390 1698 5.6550 1699 5.7390 1700 6.1180 1701 6.6680 1702 6.6400 1703 6.9730 1704 6.7180 1705 6.7590 1706 6.2250 1707 6.6580 1708 6.7430 1709 6.8290 1710 6.6720 1711 6.4810 1712 7.1440 1713 7.3450 1714 6.7880 1715 7.1780 1716 6.3890 1717 6.5100 1718 7.0570 1719 7.6820 1720 7.4720 1721 7.6530 1722 7.6640 1723 8.2070 1724 7.5910 1725 7.2290 1726 6.9940 1727 6.9910 1728 7.3330 1729 7.4200 1730 7.0370 1731 6.8910 1732 7.2880 1733 7.4060 1734 6.8200 1735 6.8960 1736 6.7410 1737 7.1900 1738 6.5880 1739 7.1420 1740 6.7880 1741 6.9300 1742 6.9340 1743 6.9210 1744 6.1590 1745 6.7200 1746 6.1730 1747 6.8270 1748 6.8750 1749 7.1810 1750 7.4570 1751 7.1990 1752 6.8000 1753 6.6080 1754 5.8850 1755 5.7650 1756 5.8120 1757 6.1160 1758 6.6630 1759 6.6110 1760 6.9070 1761 7.3290 1762 7.4380 1763 7.7600 1764 6.7220 1765 7.8190 1766 7.4270 1767 7.7460 1768 6.5150 1769 6.7270 1770 6.8290 1771 7.1120 1772 7.2790 1773 7.3040 1774 7.7230 1775 6.9230 1776 6.9250 1777 7.3170 1778 6.7610 1779 6.9750 1780 7.4200 1781 6.9020 1782 6.9820 1783 7.1260 1784 7.2600 1785 7.7370 1786 7.0570 1787 7.0940 1788 7.3770 1789 7.0420 1790 6.7060 1791 7.2670 1792 7.8810 1793 7.9060 1794 7.5550 1795 8.4100 1796 7.6340 1797 8.4190 1798 7.3630 1799 7.2440 1800 6.9410 1801 7.4000 1802 7.2880 1803 7.7940 1804 8.3090 1805 7.9790 1806 7.1010 1807 6.7840 1808 7.1440 1809 6.4190 1810 6.1410 1811 6.2000 1812 6.4810 1813 6.3480 1814 6.2910 1815 6.5540 1816 7.3360 1817 7.1190 1818 7.0850 1819 6.9730 1820 6.8840 1821 6.4490 1822 6.3890 1823 6.3960 1824 6.4240 1825 7.1830 1826 7.0600 1827 6.6540 1828 7.6320 1829 8.0200 1830 7.1370 1831 6.5950 1832 7.5340 1833 7.9080 1834 7.4270 1835 7.5980 1836 7.1920 1837 7.2790 1838 8.1470 1839 8.2300 1840 8.1380 1841 7.7890 1842 7.1080 1843 7.1260 1844 7.6460 1845 7.2490 1846 7.4110 1847 6.8930 1848 7.3470 1849 6.5150 1850 6.4990 1851 6.7200 1852 7.0830 1853 6.4010 1854 6.5100 1855 6.8660 1856 6.6630 1857 7.2350 1858 7.3900 1859 6.8110 1860 7.0600 1861 7.0050 1862 6.3070 1863 6.0820 1864 6.8680 1865 6.6610 1866 7.0760 1867 7.5360 1868 6.9690 1869 7.2130 1870 7.3110 1871 6.5560 1872 7.4980 1873 7.7050 1874 7.7190 1875 7.1940 1876 6.4990 1877 6.3980 1878 6.7880 1879 7.0730 1880 6.5170 1881 7.2260 1882 7.0030 1883 6.3140 1884 7.6590 1885 8.0150 1886 7.6140 1887 6.3760 1888 6.9640 1889 7.0550 1890 7.1370 1891 7.3170 1892 7.7710 1893 7.6280 1894 6.8860 1895 6.6380 1896 7.0160 1897 6.8890 1898 6.9730 1899 7.0870 1900 7.8050 1901 7.8760 1902 8.0650 1903 7.5960 1904 7.0230 1905 8.3050 1906 7.9880 1907 7.4720 1908 7.2170 1909 7.1300 1910 6.5490 1911 7.2380 1912 7.4090 1913 7.6570 1914 8.1040 1915 8.8700 1916 7.8400 1917 7.0730 1918 7.8400 1919 6.8930 1920 7.8940 1921 8.0200 1922 7.7320 1923 8.3570 1924 8.3070 1925 7.8260 1926 8.7470 1927 8.3340 1928 7.7440 1929 7.8970 1930 8.5170 1931 8.2090 1932 7.2630 1933 7.6940 1934 7.8740 1935 8.0080 1936 7.7920 1937 7.1510 1938 7.2060 1939 7.5040 1940 7.3110 1941 8.0060 1942 8.4710 1943 7.9150 1944 7.6000 1945 7.6250 1946 7.6340 1947 7.1400 1948 6.9640 1949 6.5950 1950 7.3810 1951 7.5910 1952 7.1120 1953 8.0270 1954 7.4360 1955 7.2760 1956 6.7820 1957 7.4770 1958 7.7480 1959 7.7120 1960 7.6140 1961 8.1220 1962 7.5550 1963 8.3180 1964 7.9970 1965 8.1630 1966 8.2160 1967 7.3110 1968 7.6910 1969 7.5890 1970 6.6810 1971 6.9120 1972 6.5720 1973 5.8240 1974 6.5970 1975 6.7910 1976 6.8610 1977 7.9860 1978 7.7990 1979 8.0110 1980 8.7330 1981 8.7060 1982 8.2590 1983 8.2820 1984 8.2360 1985 7.7990 1986 7.8880 1987 7.6160 1988 7.6480 1989 7.6980 1990 8.1430 1991 7.8920 1992 7.9400 1993 7.8400 1994 8.2610 1995 8.1610 1996 7.8010 1997 8.2890 1998 7.9600 1999 7.8080 2000 7.2290 2001 7.3770 2002 7.2700 2003 7.5770 2004 8.4120 2005 8.3370 2006 7.7550 2007 6.9960 2008 6.8500 2009 7.8080 2010 8.3800