Year Total
1800 6.5
1801 6.5
1802 6.5
1803 6.5
1804 6.5
1805 6.5
1806 6.5
1807 6.5
1808 6.5
1809 6.5
1810 6.5
1811 6.5
1812 6.5
1813 6.5
1814 6.5
1815 6.5
1816 6.5
1817 6.5
1818 6.5
1819 6.5
1820 6.5
1821 6.5
1822 6.5
1823 6.5
1824 6.5
1825 6.5
1826 6.5
1827 6.5
1828 6.5
1829 6.5
1830 6.5
1831 6.5
1832 6.5
1833 6.5
1834 6.5
1835 6.5
1836 6.5
1837 6.5
1838 6.5
1839 6.5
1840 6.5
1841 6.5
1842 6.5
1843 6.5
1844 6.5
1845 6.5
1846 6.5
1847 6.5
1848 6.5
1849 6.5
1850 6.5
1851 6.5
1852 6.5
1853 6.5
1854 6.5
1855 6.5
1856 6.5
1857 6.5
1858 6.5
1859 6.5
1860 6.5
1861 6.5
1862 6.5
1863 6.5
1864 6.5
1865 6.5
1866 6.5
1867 6.5
1868 6.5
1869 6.5
1870 6.5
1871 6.5
1872 6.5
1873 6.5
1874 6.5
1875 6.5
1876 6.5
1877 6.5
1878 6.5
1879 6.5
1880 6.5
1881 6.5
1882 6.5
1883 6.5
1884 6.5
1885 6.5
1886 6.5
1887 6.5
1888 6.5
1889 6.5
1890 6.5
1891 6.5
1892 6.5
1893 6.5
1894 6.5
1895 6.5
1896 6.5
1897 6.5
1898 6.5
1899 6.5
1900 6.5
1901 6.5
1902 6.5
1903 6.5
1904 6.5
1905 6.5
1906 6.5
1907 6.5
1908 6.5
1909 6.5
1910 6.5
1911 6.5
1912 6.5
1913 6.5
1914 6.5
1915 6.5
1916 6.5
1917 6.5
1918 6.5
1919 6.5
1920 6.5
1921 6.5
1922 6.5
1923 6.5
1924 6.5
1925 6.5
1926 6.5
1927 6.5
1928 6.5
1929 6.5
1930 6.5
1931 6.5
1932 6.5
1933 6.5
1934 6.5
1935 6.5
1936 6.5
1937 6.5
1938 6.5
1939 6.5
1940 6.5
1941 6.5
1942 6.5
1943 6.5
1944 6.5
1945 6.5
1946 6.5
1947 6.5
1948 6.49
1949 6.49
1950 6.49
1951 6.52
1952 6.58
1953 6.64
1954 6.7
1955 6.76
1956 6.82
1957 6.89
1958 6.94
1959 7
1960 7.04
1961 7.07
1962 7.09
1963 7.09
1964 7.07
1965 7.03
1966 6.97
1967 6.9
1968 6.82
1969 6.74
1970 6.65
1971 6.55
1972 6.46
1973 6.36
1974 6.26
1975 6.16
1976 6.06
1977 5.97
1978 5.88
1979 5.78
1980 5.68
1981 5.57
1982 5.44
1983 5.29
1984 5.12
1985 4.94
1986 4.75
1987 4.57
1988 4.39
1989 4.22
1990 4.06
1991 3.9
1992 3.75
1993 3.6
1994 3.45
1995 3.3
1996 3.16
1997 3.04
1998 2.93
1999 2.85
2000 2.78
2001 2.72
2002 2.68
2003 2.64
2004 2.61
2005 2.59
2006 2.57
2007 2.56
2008 2.56
2009 2.57
2010 2.58
2011 2.58
2012 2.58
2013 2.57
2014 2.56
2015 2.53
2016 2.49
2017 2.45
2018 2.42