Year Measure
1820 418.1
1821 420.1
1822 422
1823 424
1824 426
1825 428
1826 430
1827 432
1828 434.1
1829 436.1
1830 438.1
1831 440.2
1832 442.3
1833 444.3
1834 446.4
1835 448.5
1836 450.6
1837 452.7
1838 454.8
1839 457
1840 459.1
1841 461.3
1842 463.4
1843 465.6
1844 467.8
1845 470
1846 472.2
1847 474.4
1848 476.6
1849 478.9
1850 481.1
1851 483.4
1852 485.6
1853 487.9
1854 490.2
1855 492.5
1856 494.8
1857 497.1
1858 499.5
1859 501.8
1860 504.1
1861 506.5
1862 508.9
1863 511.3
1864 513.7
1865 516.1
1866 518.5
1867 520.9
1868 523.4
1869 525.8
1870 528.3
1871 530.8
1872 533.3
1873 535.8
1874 538.3
1875 540.8
1876 543.3
1877 545.9
1878 548.4
1879 551
1880 553.6
1881 556.2
1882 558.8
1883 561.4
1884 564.1
1885 566.7
1886 569.4
1887 572
1888 574.7
1889 577.4
1890 580.1
1891 582.8
1892 585.6
1893 588.3
1894 591.1
1895 593.8
1896 596.6
1897 599.4
1898 602.2
1899 605.1
1900 607.9
1901 610.7
1902 613.6
1903 616.5
1904 619.4
1905 622.3
1906 625.2
1907 628.1
1908 631.1
1909 634
1910 637
1911 640
1912 643
1913 646
1914 650.8
1915 655.5
1916 660.4
1917 665.2
1918 670.1
1919 675
1920 680
1921 685
1922 690
1923 695.1
1924 700.2
1925 705.3
1926 710.5
1927 715.7
1928 721
1929 726.3
1930 731.6
1931 737
1932 742.4
1933 747.9
1934 753.4
1935 758.9
1936 764.5
1937 770.1
1938 775.8
1939 781.5
1940 787.2
1941 793
1942 798.8
1943 804.7
1944 810.6
1945 816.6
1946 822.6
1947 828.6
1948 834.7
1949 840.9
1950 847
1951 863.1
1952 873.7
1953 888.7
1954 903.7
1955 917.2
1956 929.8
1957 942.5
1958 953.6
1959 969.1
1960 978.4
1961 997.1
1962 1010
1963 1026
1964 1046
1965 1062
1966 1149
1967 1247
1968 1354
1969 1462
1970 1573
1971 1816
1972 2323
1973 2729
1974 3159
1975 2974
1976 3358
1977 3300
1978 3736
1979 3919
1980 4289
1981 4515
1982 4671
1983 5214
1984 5594
1985 5805
1986 6045
1987 6370
1988 7143
1989 7821
1990 8036
1991 8175
1992 8164
1993 8068
1994 8106
1995 8242
1996 8500
1997 8875
1998 9228
1999 9665
2000 10370
2001 10820
2002 11290
2003 11690
2004 12030
2005 12380
2006 12910
2007 13350
2008 13590
2009 12790
2010 13530
2011 14050
2012 14470
2013 14860
2014 15290
2015 15770
2016 16220
2017 16680
2018 17140
2019 17580