Year Total 1800 6.96 1801 6.96 1802 6.96 1803 6.96 1804 6.96 1805 6.96 1806 6.96 1807 6.96 1808 6.96 1809 6.96 1810 6.96 1811 6.96 1812 6.96 1813 6.96 1814 6.96 1815 6.96 1816 6.96 1817 6.96 1818 6.96 1819 6.96 1820 6.96 1821 6.96 1822 6.96 1823 6.96 1824 6.96 1825 6.96 1826 6.96 1827 6.96 1828 6.96 1829 6.96 1830 6.96 1831 6.96 1832 6.96 1833 6.96 1834 6.96 1835 6.96 1836 6.96 1837 6.96 1838 6.96 1839 6.96 1840 6.96 1841 6.96 1842 6.96 1843 6.96 1844 6.96 1845 6.96 1846 6.96 1847 6.96 1848 6.96 1849 6.96 1850 6.96 1851 6.96 1852 6.96 1853 6.96 1854 6.96 1855 6.96 1856 6.96 1857 6.96 1858 6.96 1859 6.96 1860 6.96 1861 6.96 1862 6.96 1863 6.96 1864 6.96 1865 6.96 1866 6.96 1867 6.96 1868 6.96 1869 6.96 1870 6.96 1871 6.96 1872 6.96 1873 6.96 1874 6.96 1875 6.96 1876 6.96 1877 6.96 1878 6.96 1879 6.96 1880 6.96 1881 6.96 1882 6.96 1883 6.96 1884 6.96 1885 6.96 1886 6.96 1887 6.96 1888 6.96 1889 6.96 1890 6.96 1891 6.96 1892 6.96 1893 6.96 1894 6.96 1895 6.96 1896 6.96 1897 6.96 1898 6.96 1899 6.96 1900 6.96 1901 6.96 1902 6.96 1903 6.96 1904 6.96 1905 6.96 1906 6.96 1907 6.96 1908 6.96 1909 6.96 1910 6.96 1911 6.96 1912 6.96 1913 6.96 1914 6.96 1915 6.96 1916 6.96 1917 6.96 1918 6.96 1919 6.96 1920 6.96 1921 6.96 1922 6.96 1923 6.96 1924 6.96 1925 6.96 1926 6.96 1927 6.96 1928 6.96 1929 6.95 1930 6.95 1931 6.95 1932 6.95 1933 6.95 1934 6.95 1935 6.95 1936 6.94 1937 6.94 1938 6.94 1939 6.94 1940 6.94 1941 6.94 1942 6.94 1943 6.93 1944 6.93 1945 6.93 1946 6.93 1947 6.93 1948 6.93 1949 6.93 1950 6.92 1951 6.94 1952 6.96 1953 6.98 1954 6.99 1955 6.99 1956 6.98 1957 6.97 1958 6.95 1959 6.93 1960 6.9 1961 6.87 1962 6.84 1963 6.81 1964 6.78 1965 6.75 1966 6.73 1967 6.71 1968 6.69 1969 6.67 1970 6.65 1971 6.64 1972 6.62 1973 6.62 1974 6.61 1975 6.61 1976 6.61 1977 6.63 1978 6.64 1979 6.66 1980 6.68 1981 6.69 1982 6.69 1983 6.68 1984 6.67 1985 6.64 1986 6.6 1987 6.55 1988 6.5 1989 6.45 1990 6.39 1991 6.32 1992 6.23 1993 6.14 1994 6.03 1995 5.91 1996 5.79 1997 5.67 1998 5.55 1999 5.43 2000 5.33 2001 5.23 2002 5.15 2003 5.07 2004 5.01 2005 4.94 2006 4.88 2007 4.82 2008 4.75 2009 4.68 2010 4.61 2011 4.53 2012 4.44 2013 4.36 2014 4.29 2015 4.21 2016 4.13 2017 4.06 2018 3.99