Year Years 1800 512.4 1801 512.4 1802 512.4 1803 512.4 1804 512.4 1805 512.4 1806 512.4 1807 512.4 1808 512.4 1809 512.4 1810 512.4 1811 512.4 1812 512.4 1813 512.4 1814 512.4 1815 512.4 1816 512.4 1817 512.4 1818 512.4 1819 512.4 1820 512.4 1821 512.4 1822 512.4 1823 512.4 1824 512.4 1825 512.4 1826 512.4 1827 512.4 1828 512.4 1829 512.4 1830 512.4 1831 512.4 1832 512.4 1833 512.4 1834 512.4 1835 512.4 1836 512.4 1837 512.4 1838 512.4 1839 512.4 1840 512.4 1841 512.4 1842 512.4 1843 512.4 1844 512.4 1845 512.4 1846 512.4 1847 512.4 1848 512.4 1849 512.4 1850 512.4 1851 512.4 1852 512.4 1853 512.4 1854 512.4 1855 512.4 1856 512.4 1857 512.4 1858 512.4 1859 512.4 1860 512.4 1861 512.4 1862 512.4 1863 512.4 1864 512.4 1865 512.4 1866 512.4 1867 512.4 1868 512.4 1869 512.4 1870 512.4 1871 512.4 1872 512.4 1873 512.4 1874 512.4 1875 512.4 1876 512.4 1877 512.4 1878 512.4 1879 512.4 1880 512.4 1881 512.4 1882 512.4 1883 512.4 1884 512.4 1885 512.4 1886 512.4 1887 512.4 1888 512.4 1889 512.4 1890 512.4 1891 512.4 1892 512.4 1893 512.4 1894 512.4 1895 512.4 1896 512.3 1897 512.1 1898 511.9 1899 511.7 1900 511.3 1901 510.9 1902 510.3 1903 509.7 1904 509.1 1905 508.3 1906 507.4 1907 506.5 1908 505.5 1909 504.5 1910 503.3 1911 502.2 1912 501 1913 499.8 1914 498.6 1915 497.4 1916 496.2 1917 495 1918 493.8 1919 492.6 1920 491.4 1921 490.2 1922 489 1923 492.1 1924 493.8 1925 497 1926 498.7 1927 501.9 1928 496.2 1929 492.1 1930 486.5 1931 482.4 1932 476.9 1933 472.9 1934 467.6 1935 463.6 1936 458.3 1937 454.4 1938 449.2 1939 444.1 1940 439 1950 345.6 1951 339.9 1952 334.3 1953 328.8 1954 323.7 1955 318.7 1956 313.9 1957 309.7 1958 306.4 1959 304 1960 302.4 1961 301.6 1962 301.3 1963 301.4 1964 301.5 1965 301.2 1966 300.5 1967 299.2 1968 297.2 1969 294.2 1970 290.1 1971 285 1972 278.6 1973 271 1974 262.2 1975 252.5 1976 242.2 1977 231.5 1978 221.3 1979 212.5 1980 205 1981 198.6 1982 192.9 1983 187.2 1984 180.6 1985 173.3 1986 165.3 1987 157.2 1988 150.1 1989 144.7 1990 141.1 1991 139.5 1992 139.3 1993 140.3 1994 141.8 1995 143.2 1996 144.5 1997 145 1998 144.2 1999 141.6 2000 137 2001 130.7 2002 123 2003 114.6 2004 106.3 2005 98.1 2006 90.6 2007 83.7 2008 77.3 2009 71.4 2010 66.3 2011 61.9 2012 58.4 2013 55.3