Year Measure
1820 446.4
1821 448.5
1822 450.6
1823 452.7
1824 454.8
1825 457
1826 459.1
1827 461.3
1828 463.4
1829 465.6
1830 467.8
1831 470
1832 472.2
1833 474.4
1834 476.6
1835 478.8
1836 481.1
1837 483.3
1838 485.6
1839 487.9
1840 490.2
1841 492.5
1842 494.8
1843 497.1
1844 499.4
1845 501.8
1846 504.1
1847 506.5
1848 508.9
1849 511.3
1850 513.7
1851 516.1
1852 518.5
1853 520.9
1854 523.4
1855 525.8
1856 528.3
1857 530.8
1858 533.2
1859 535.7
1860 538.3
1861 540.8
1862 543.3
1863 545.9
1864 548.4
1865 551
1866 553.6
1867 556.2
1868 558.8
1869 561.4
1870 564
1871 566.7
1872 569.3
1873 572
1874 574.7
1875 577.4
1876 580.1
1877 582.8
1878 585.5
1879 588.3
1880 591
1881 593.8
1882 596.6
1883 599.4
1884 602.2
1885 605
1886 607.9
1887 610.7
1888 613.6
1889 616.5
1890 619.4
1891 622.3
1892 625.2
1893 628.1
1894 631.1
1895 634
1896 637
1897 640
1898 643
1899 646
1900 649
1901 652.1
1902 655.1
1903 658.2
1904 661.3
1905 664.4
1906 667.5
1907 670.6
1908 673.8
1909 676.9
1910 680.1
1911 683.3
1912 686.5
1913 689.7
1914 701.9
1915 714.3
1916 726.9
1917 739.8
1918 752.9
1919 766.2
1920 779.7
1921 793.5
1922 807.5
1923 821.8
1924 836.3
1925 851.1
1926 866.1
1927 881.5
1928 897
1929 912.9
1930 929
1931 945.4
1932 962.2
1933 979.2
1934 996.5
1935 1014
1936 1032
1937 1050
1938 1069
1939 1088
1940 1107
1941 1126
1942 1146
1943 1167
1944 1187
1945 1208
1946 1230
1947 1251
1948 1273
1949 1296
1950 1319
1951 1351
1952 1383
1953 1414
1954 1445
1955 1476
1956 1507
1957 1537
1958 1567
1959 1597
1960 1582
1961 1612
1962 1540
1963 1506
1964 1500
1965 1480
1966 1441
1967 1466
1968 1449
1969 1491
1970 1522
1971 1443
1972 1381
1973 1415
1974 1346
1975 1336
1976 1359
1977 1432
1978 1420
1979 1305
1980 1259
1981 1245
1982 1235
1983 1130
1984 1173
1985 1151
1986 1145
1987 1091
1988 1081
1989 1090
1990 1099
1991 1061
1992 965.4
1993 939.4
1994 973.1
1995 1002
1996 907.2
1997 955.8
1998 971.2
1999 985.6
2000 983.8
2001 972.6
2002 953.5
2003 867.1
2004 866.2
2005 871.3
2006 894.9
2007 917.8
2008 918.3
2009 900.9
2010 905.7
2011 912.8
2012 932
2013 584.6
2014 581.7
2015 600.8
2016 622.8
2017 645.6
2018 669.9
2019 694.5