Year Years 1800 374 1801 374 1802 374 1803 374 1804 374 1805 374 1806 374 1807 374 1808 374 1809 374 1810 374 1811 374 1812 374 1813 374 1814 374 1815 374 1816 374 1817 374 1818 374 1819 374 1820 374 1821 374 1822 374 1823 374 1824 374 1825 374 1826 374 1827 374 1828 374 1829 374 1830 374 1831 374 1832 374 1833 374 1834 374 1835 374 1836 374 1837 374 1838 374 1839 374 1840 374 1841 374 1842 374 1843 374 1844 374 1845 374 1846 374 1847 374 1848 374 1849 374 1850 374 1851 374 1852 374 1853 374 1854 374 1855 374 1856 374 1857 374 1858 374 1859 374 1860 374 1861 374 1862 374 1863 374 1864 374 1865 374 1866 374 1867 374 1868 374 1869 374 1870 374 1871 374 1872 374 1873 374 1874 374 1875 374 1876 374 1877 374 1878 374 1879 374 1880 374 1881 374 1882 374 1883 374 1884 374 1885 374 1886 374 1887 374 1888 374 1889 374 1890 374 1891 374 1892 374 1893 374 1894 374 1895 374 1896 373.9 1897 373.8 1898 373.7 1899 373.5 1900 373.2 1901 372.9 1902 372.5 1903 372.1 1904 371.6 1905 371 1906 370.4 1907 369.7 1908 369 1909 368.2 1910 367.4 1911 366.5 1912 365.7 1913 364.8 1914 363.9 1915 363 1916 362.2 1917 361.3 1918 360.4 1919 359.5 1920 358.6 1921 357.8 1922 356.9 1923 356 1924 355.1 1925 354.3 1926 353.4 1927 352.5 1928 351.6 1929 350.8 1930 349.9 1931 349 1932 348.1 1933 330.8 1934 314.1 1935 297.8 1936 282.1 1937 265.9 1938 251.2 1939 236.9 1940 223 1941 209.5 1951 93.4 1952 92.6 1953 91.9 1954 91.1 1955 90.3 1956 89.5 1957 88.8 1958 87.9 1959 87.1 1960 86.3 1961 85.5 1962 84.7 1963 84 1964 83.2 1965 82.5 1966 81.7 1967 80.9 1968 80.1 1969 79.2 1970 78.2 1971 77.2 1972 76.1 1973 74.8 1974 73.5 1975 72 1976 70.6 1977 69.1 1978 67.5 1979 65.8 1980 64.1 1981 62.3 1982 60.5 1983 58.6 1984 56.7 1985 54.9 1986 53.1 1987 51.3 1988 49.6 1989 47.9 1990 46.2 1991 44.7 1992 43.1 1993 41.7 1994 40.3 1995 39 1996 37.8 1997 36.7 1998 35.6 1999 34.6 2000 33.5 2001 32.5 2002 31.5 2003 30.5 2004 29.4 2005 28.5 2006 27.6 2007 26.7 2008 25.8 2009 25 2010 24.2 2011 23.4 2012 22.7 2013 21.9