Year Total 1800 6.23 1801 6.23 1802 6.23 1803 6.23 1804 6.23 1805 6.23 1806 6.23 1807 6.23 1808 6.23 1809 6.23 1810 6.23 1811 6.23 1812 6.23 1813 6.23 1814 6.23 1815 6.23 1816 6.23 1817 6.23 1818 6.23 1819 6.23 1820 6.23 1821 6.23 1822 6.23 1823 6.23 1824 6.23 1825 6.23 1826 6.23 1827 6.23 1828 6.23 1829 6.23 1830 6.23 1831 6.23 1832 6.23 1833 6.23 1834 6.23 1835 6.23 1836 6.23 1837 6.23 1838 6.23 1839 6.23 1840 6.23 1841 6.23 1842 6.23 1843 6.23 1844 6.23 1845 6.23 1846 6.23 1847 6.23 1848 6.23 1849 6.23 1850 6.23 1851 6.23 1852 6.23 1853 6.23 1854 6.23 1855 6.23 1856 6.23 1857 6.23 1858 6.23 1859 6.23 1860 6.23 1861 6.23 1862 6.23 1863 6.23 1864 6.23 1865 6.23 1866 6.23 1867 6.23 1868 6.23 1869 6.23 1870 6.23 1871 6.23 1872 6.23 1873 6.23 1874 6.23 1875 6.23 1876 6.23 1877 6.23 1878 6.23 1879 6.23 1880 6.23 1881 6.23 1882 6.23 1883 6.23 1884 6.23 1885 6.23 1886 6.23 1887 6.23 1888 6.23 1889 6.23 1890 6.23 1891 6.23 1892 6.23 1893 6.23 1894 6.23 1895 6.23 1896 6.23 1897 6.23 1898 6.23 1899 6.23 1900 6.23 1901 6.23 1902 6.23 1903 6.23 1904 6.23 1905 6.23 1906 6.23 1907 6.23 1908 6.23 1909 6.23 1910 6.23 1911 6.23 1912 6.23 1913 6.23 1914 6.23 1915 6.23 1916 6.23 1917 6.23 1918 6.23 1919 6.23 1920 6.23 1921 6.23 1922 6.23 1923 6.23 1924 6.23 1925 6.23 1926 6.23 1927 6.23 1928 6.23 1929 6.23 1930 6.23 1931 6.23 1932 6.23 1933 6.23 1934 6.23 1935 6.23 1936 6.23 1937 6.23 1938 6.23 1939 6.23 1940 6.23 1941 6.23 1942 6.23 1943 6.23 1944 6.23 1945 6.23 1946 6.23 1947 6.23 1948 6.23 1949 6.23 1950 6.23 1951 6.23 1952 6.24 1953 6.24 1954 6.24 1955 6.25 1956 6.25 1957 6.26 1958 6.27 1959 6.27 1960 6.28 1961 6.28 1962 6.28 1963 6.28 1964 6.27 1965 6.26 1966 6.24 1967 6.23 1968 6.21 1969 6.19 1970 6.16 1971 6.14 1972 6.11 1973 6.08 1974 6.04 1975 6 1976 5.95 1977 5.9 1978 5.84 1979 5.77 1980 5.69 1981 5.61 1982 5.52 1983 5.42 1984 5.31 1985 5.21 1986 5.11 1987 5.02 1988 4.93 1989 4.86 1990 4.8 1991 4.76 1992 4.72 1993 4.7 1994 4.68 1995 4.67 1996 4.65 1997 4.63 1998 4.6 1999 4.57 2000 4.53 2001 4.48 2002 4.42 2003 4.37 2004 4.32 2005 4.26 2006 4.21 2007 4.16 2008 4.1 2009 4.04 2010 3.99 2011 3.93 2012 3.87 2013 3.81 2014 3.76 2015 3.71 2016 3.66 2017 3.61 2018 3.56