Year Years 1800 36.4 1801 36.4 1802 36.4 1803 36.4 1804 36.4 1805 36.4 1806 36.4 1807 36.4 1808 36.4 1809 36.4 1810 36.4 1811 36.4 1812 36.4 1813 36.4 1814 36.4 1815 36.4 1816 36.4 1817 36.4 1818 36.4 1819 36.4 1820 36.4 1821 36.4 1822 36.4 1823 36.4 1824 36.4 1825 36.4 1826 36.4 1827 36.4 1828 36.4 1829 36.4 1830 36.4 1831 36.4 1832 36.4 1833 36.4 1834 36.4 1835 36.4 1836 36.4 1837 36.4 1838 36.4 1839 36.4 1840 36.4 1841 36.4 1842 36.4 1843 36.4 1844 36.4 1845 36.4 1846 36.4 1847 36.4 1848 36.4 1849 36.4 1850 36.4 1851 36.4 1852 36.4 1853 36.4 1854 36.4 1855 36.4 1856 36.4 1857 36.4 1858 36.4 1859 36.4 1860 36.4 1861 36.4 1862 36.4 1863 36.4 1864 36.4 1865 36.4 1866 36.4 1867 36.4 1868 36.4 1869 36.4 1870 36.4 1871 36.4 1872 36.4 1873 36.4 1874 36.4 1875 36.4 1876 36.4 1877 36.4 1878 36.4 1879 36.41 1880 36.41 1881 36.41 1882 36.41 1883 36.41 1884 36.41 1885 36.41 1886 36.41 1887 36.41 1888 36.41 1889 36.41 1890 36.41 1891 36.41 1892 36.41 1893 36.41 1894 36.41 1895 36.41 1896 36.72 1897 37.02 1898 37.32 1899 37.62 1900 37.92 1901 38.22 1902 38.52 1903 38.82 1904 39.12 1905 39.42 1906 39.72 1907 40.02 1908 40.32 1909 40.63 1910 40.93 1911 41.23 1912 41.53 1913 41.83 1914 42.13 1915 42.43 1916 42.73 1917 43.03 1918 31.88 1919 43.63 1920 43.94 1921 44.24 1922 44.87 1923 45.51 1924 46.14 1925 46.77 1926 47.41 1927 48.04 1928 48.68 1929 49.32 1930 49.95 1931 50.42 1932 50.89 1933 51.36 1934 51.84 1935 52.31 1936 52.79 1937 53.26 1938 53.85 1939 54.16 1940 54.06 1941 53.86 1942 52.06 1943 47.56 1944 42.55 1945 40.55 1946 54.07 1947 58.07 1948 59.07 1949 60.38 1950 60.97 1951 61.39 1952 64.44 1953 65.75 1954 66.8 1955 67.93 1956 68.46 1957 67.54 1958 69.45 1959 69.13 1960 70.45 1961 70.89 1962 70.43 1963 70.81 1964 71.2 1965 70.41 1966 70.55 1967 71.09 1968 70.61 1969 69.92 1970 69.85 1971 69.94 1972 70.13 1973 70.09 1974 70.29 1975 70.4 1976 70.49 1977 70.6 1978 70.55 1979 70.69 1980 70.57 1981 70.68 1982 70.83 1983 70.7 1984 70.81 1985 70.83 1986 70.99 1987 71.04 1988 71.15 1989 71.07 1990 71.07 1991 71.16 1992 71.5 1993 71.91 1994 72.25 1995 72.38 1996 72.72 1997 72.75 1998 72.77 1999 73 2000 73.26 2001 73.55 2002 73.77 2003 73.9 2004 74.13 2005 74.2 2006 74.4 2007 74.54 2008 74.86 2009 75.11 2010 75.52 2011 75.86 2012 76.17 2013 76.47 2014 76.74 2015 76.84 2016 76.91 2017 77.04 2018 77.16