Year Total
1800 6.51
1801 6.51
1802 6.51
1803 6.51
1804 6.51
1805 6.51
1806 6.51
1807 6.51
1808 6.51
1809 6.51
1810 6.51
1811 6.51
1812 6.51
1813 6.51
1814 6.51
1815 6.51
1816 6.51
1817 6.51
1818 6.51
1819 6.51
1820 6.51
1821 6.51
1822 6.51
1823 6.51
1824 6.51
1825 6.51
1826 6.51
1827 6.51
1828 6.51
1829 6.51
1830 6.51
1831 6.51
1832 6.51
1833 6.51
1834 6.51
1835 6.51
1836 6.51
1837 6.51
1838 6.51
1839 6.51
1840 6.51
1841 6.51
1842 6.51
1843 6.51
1844 6.51
1845 6.51
1846 6.51
1847 6.51
1848 6.51
1849 6.51
1850 6.51
1851 6.51
1852 6.51
1853 6.51
1854 6.51
1855 6.51
1856 6.51
1857 6.51
1858 6.51
1859 6.51
1860 6.51
1861 6.51
1862 6.51
1863 6.51
1864 6.51
1865 6.51
1866 6.51
1867 6.51
1868 6.51
1869 6.51
1870 6.51
1871 6.51
1872 6.51
1873 6.51
1874 6.51
1875 6.51
1876 6.51
1877 6.51
1878 6.51
1879 6.51
1880 6.51
1881 6.51
1882 6.51
1883 6.51
1884 6.51
1885 6.51
1886 6.51
1887 6.51
1888 6.51
1889 6.51
1890 6.51
1891 6.51
1892 6.51
1893 6.51
1894 6.51
1895 6.51
1896 6.51
1897 6.51
1898 6.51
1899 6.51
1900 6.51
1901 6.51
1902 6.51
1903 6.51
1904 6.51
1905 6.51
1906 6.51
1907 6.51
1908 6.51
1909 6.51
1910 6.51
1911 6.51
1912 6.51
1913 6.51
1914 6.51
1915 6.51
1916 6.51
1917 6.51
1918 6.51
1919 6.51
1920 6.51
1921 6.51
1922 6.51
1923 6.51
1924 6.51
1925 6.51
1926 6.46
1927 6.41
1928 6.36
1929 6.31
1930 6.26
1931 6.2
1932 6.15
1933 6.1
1934 6.05
1935 6
1936 5.95
1937 5.9
1938 5.85
1939 5.79
1940 5.74
1941 5.69
1942 5.64
1943 5.59
1944 5.54
1945 5.49
1946 5.44
1947 5.38
1948 5.33
1949 5.28
1950 5.23
1951 5.24
1952 5.27
1953 5.3
1954 5.33
1955 5.37
1956 5.4
1957 5.44
1958 5.48
1959 5.53
1960 5.57
1961 5.62
1962 5.67
1963 5.72
1964 5.78
1965 5.83
1966 5.88
1967 5.94
1968 5.99
1969 6.04
1970 6.09
1971 6.14
1972 6.19
1973 6.23
1974 6.26
1975 6.29
1976 6.32
1977 6.33
1978 6.34
1979 6.34
1980 6.34
1981 6.32
1982 6.3
1983 6.28
1984 6.25
1985 6.22
1986 6.19
1987 6.16
1988 6.14
1989 6.12
1990 6.11
1991 6.09
1992 6.08
1993 6.07
1994 6.05
1995 6.04
1996 6.02
1997 6
1998 5.98
1999 5.97
2000 5.95
2001 5.93
2002 5.91
2003 5.88
2004 5.86
2005 5.84
2006 5.81
2007 5.79
2008 5.76
2009 5.74
2010 5.71
2011 5.68
2012 5.64
2013 5.6
2014 5.54
2015 5.49
2016 5.43
2017 5.36
2018 5.29