Year Total 1800 5.47 1801 5.47 1802 5.47 1803 5.47 1804 5.47 1805 5.47 1806 5.47 1807 5.47 1808 5.47 1809 5.47 1810 5.47 1811 5.47 1812 5.47 1813 5.47 1814 5.47 1815 5.47 1816 5.47 1817 5.47 1818 5.47 1819 5.47 1820 5.47 1821 5.47 1822 5.47 1823 5.47 1824 5.47 1825 5.47 1826 5.47 1827 5.47 1828 5.47 1829 5.47 1830 5.47 1831 5.47 1832 5.47 1833 5.47 1834 5.47 1835 5.47 1836 5.47 1837 5.47 1838 5.47 1839 5.47 1840 5.47 1841 5.47 1842 5.47 1843 5.47 1844 5.47 1845 5.47 1846 5.47 1847 5.47 1848 5.47 1849 5.47 1850 5.47 1851 5.47 1852 5.47 1853 5.47 1854 5.47 1855 5.47 1856 5.47 1857 5.47 1858 5.47 1859 5.47 1860 5.47 1861 5.47 1862 5.47 1863 5.47 1864 5.47 1865 5.47 1866 5.47 1867 5.47 1868 5.47 1869 5.47 1870 5.47 1871 5.47 1872 5.47 1873 5.47 1874 5.47 1875 5.47 1876 5.47 1877 5.47 1878 5.47 1879 5.47 1880 5.47 1881 5.47 1882 5.47 1883 5.47 1884 5.47 1885 5.47 1886 5.47 1887 5.47 1888 5.47 1889 5.47 1890 5.47 1891 5.47 1892 5.47 1893 5.47 1894 5.47 1895 5.47 1896 5.47 1897 5.47 1898 5.47 1899 5.47 1900 5.47 1901 5.47 1902 5.47 1903 5.47 1904 5.47 1905 5.47 1906 5.47 1907 5.47 1908 5.47 1909 5.47 1910 5.47 1911 5.47 1912 5.47 1913 5.47 1914 5.47 1915 5.47 1916 5.47 1917 5.47 1918 5.47 1919 5.47 1920 5.47 1921 5.47 1922 5.47 1923 5.47 1924 5.47 1925 5.47 1926 5.43 1927 5.39 1928 5.35 1929 5.32 1930 5.28 1931 5.24 1932 5.2 1933 5.16 1934 5.12 1935 5.08 1936 5.04 1937 5 1938 4.96 1939 4.92 1940 4.88 1941 4.84 1942 4.8 1943 4.76 1944 4.72 1945 4.68 1946 4.63 1947 4.59 1948 4.55 1949 4.51 1950 4.47 1951 4.44 1952 4.41 1953 4.42 1954 4.46 1955 4.54 1956 4.64 1957 4.75 1958 4.86 1959 4.96 1960 5.01 1961 5.03 1962 4.98 1963 4.86 1964 4.67 1965 4.42 1966 4.15 1967 3.89 1968 3.65 1969 3.45 1970 3.28 1971 3.15 1972 3.02 1973 2.89 1974 2.75 1975 2.61 1976 2.46 1977 2.31 1978 2.18 1979 2.05 1980 1.94 1981 1.84 1982 1.75 1983 1.66 1984 1.58 1985 1.5 1986 1.44 1987 1.39 1988 1.35 1989 1.32 1990 1.3 1991 1.27 1992 1.25 1993 1.23 1994 1.2 1995 1.16 1996 1.12 1997 1.08 1998 1.04 1999 1.01 2000 0.98 2001 0.97 2002 0.96 2003 0.95 2004 0.96 2005 0.97 2006 0.99 2007 1.02 2008 1.05 2009 1.08 2010 1.12 2011 1.15 2012 1.18 2013 1.22 2014 1.24 2015 1.27 2016 1.3 2017 1.32 2018 1.34