Year Years 1800 420 1801 420 1802 420 1803 420 1804 420 1805 420 1806 420 1807 420 1808 420 1809 420 1810 420 1811 420 1812 420 1813 420 1814 420 1815 420 1816 420 1817 420 1818 420 1819 420 1820 420 1821 420 1822 420 1823 420 1824 420 1825 420 1826 420 1827 420 1828 420 1829 420 1830 420 1831 420 1832 420 1833 420 1834 420 1835 420 1836 420 1837 420 1838 420 1839 420 1840 420 1841 420 1842 420 1843 420 1844 420 1845 420 1846 420 1847 420 1848 420 1849 420 1850 420 1851 420 1852 420 1853 420 1854 420 1855 420 1856 420 1857 420 1858 420 1859 420 1860 420 1861 420 1862 420 1863 420 1864 420 1865 420 1866 420 1867 420 1868 420 1869 420 1870 420 1871 420 1872 420 1873 420 1874 420 1875 420 1876 420 1877 420 1878 420 1879 420 1880 420 1881 420 1882 420 1883 420 1884 420 1885 420 1886 420 1887 420 1888 420 1889 420 1890 420 1891 420 1892 420 1893 420 1894 420 1895 420 1896 419.9 1897 419.8 1898 419.7 1899 419.4 1900 419.1 1901 418.8 1902 418.3 1903 417.9 1904 417.3 1905 416.7 1906 416 1907 415.2 1908 414.4 1909 413.5 1910 412.6 1911 411.6 1912 410.7 1913 409.7 1914 408.7 1915 407.7 1916 406.7 1917 405.8 1918 404.8 1919 403.8 1920 402.8 1921 401.8 1922 400.8 1923 399.8 1924 398.9 1925 397.9 1926 396.9 1927 395.9 1928 394.9 1929 393.9 1930 392.9 1931 387.1 1932 381.4 1933 376.9 1934 371.3 1935 365.8 1936 360.2 1937 354.8 1938 350.6 1939 345.3 1940 340 1941 334.8 1942 329.6 1943 325.6 1944 320.5 1954 250.1 1955 244.5 1956 238.9 1957 233.4 1958 227.6 1959 221.5 1960 216.1 1961 211.9 1962 208.8 1963 206.5 1964 205.4 1965 205.2 1966 206 1967 207.6 1968 210.1 1969 213.1 1970 216.6 1971 220.3 1972 224.3 1973 229.6 1974 235.9 1975 241.8 1976 245.9 1977 246.2 1978 240.8 1979 228.9 1980 214 1981 198 1982 183.3 1983 171.9 1984 164 1985 158.4 1986 153.9 1987 150.6 1988 148.9 1989 149.2 1990 151.8 1991 156.8 1992 163.5 1993 179 1994 287.5 1995 253.2 1996 190.7 1997 215.7 1998 230.9 1999 198.9 2000 181.9 2001 167.5 2002 151.2 2003 135.2 2004 120.1 2005 106.4 2006 94.6 2007 84.3 2008 75.8 2009 69.1 2010 63.6 2011 58.7 2012 54.9 2013 52