Year Years
1800 30.6
1801 30.6
1802 30.6
1803 30.6
1804 30.6
1805 30.6
1806 30.6
1807 30.6
1808 30.6
1809 30.6
1810 30.6
1811 30.6
1812 30.6
1813 30.6
1814 30.6
1815 30.6
1816 30.6
1817 30.6
1818 30.6
1819 30.6
1820 30.6
1821 30.6
1822 30.6
1823 30.6
1824 30.6
1825 30.6
1826 30.6
1827 30.6
1828 30.6
1829 30.6
1830 30.6
1831 30.6
1832 30.6
1833 30.6
1834 30.6
1835 30.6
1836 30.6
1837 30.6
1838 30.6
1839 30.6
1840 30.6
1841 30.6
1842 30.6
1843 30.6
1844 30.6
1845 30.6
1846 30.6
1847 30.6
1848 30.6
1849 30.6
1850 30.6
1851 30.6
1852 30.6
1853 30.6
1854 30.6
1855 30.6
1856 30.6
1857 30.6
1858 30.6
1859 30.6
1860 30.6
1861 30.6
1862 30.6
1863 30.6
1864 30.6
1865 30.6
1866 30.6
1867 30.6
1868 30.6
1869 30.6
1870 30.6
1871 30.6
1872 30.6
1873 30.6
1874 30.6
1875 30.6
1876 30.6
1877 30.6
1878 30.61
1879 30.61
1880 30.61
1881 30.61
1882 30.61
1883 30.61
1884 30.61
1885 30.61
1886 30.61
1887 30.61
1888 30.61
1889 30.61
1890 30.61
1891 30.61
1892 30.62
1893 30.62
1894 30.62
1895 30.62
1896 30.62
1897 30.62
1898 30.62
1899 30.62
1900 30.62
1901 30.62
1902 30.62
1903 30.62
1904 30.62
1905 30.62
1906 30.63
1907 30.63
1908 30.63
1909 30.63
1910 30.63
1911 30.63
1912 30.63
1913 30.63
1914 30.63
1915 30.63
1916 30.63
1917 30.63
1918 19.63
1919 30.63
1920 30.64
1921 30.64
1922 30.64
1923 30.64
1924 30.64
1925 30.64
1926 30.64
1927 30.64
1928 30.64
1929 30.64
1930 30.64
1931 31.78
1932 32.94
1933 34.08
1934 35.23
1935 36.37
1936 37.53
1937 38.67
1938 39.81
1939 40.96
1940 42.11
1941 41.87
1942 36.16
1943 38.56
1944 38.37
1945 38.17
1946 45.08
1947 48.08
1948 50.59
1949 52.09
1950 53.59
1951 53.92
1952 54.57
1953 55.23
1954 55.88
1955 56.51
1956 57.14
1957 57.77
1958 58.39
1959 58.99
1960 59.59
1961 60.17
1962 60.74
1963 61.28
1964 61.8
1965 62.32
1966 62.8
1967 63.27
1968 63.72
1969 64.17
1970 64.6
1971 65.09
1972 65.6
1973 66.07
1974 66.51
1975 66.9
1976 67.36
1977 67.51
1978 68.13
1979 68.56
1980 68.92
1981 69.24
1982 69.57
1983 69.88
1984 70.2
1985 70.54
1986 70.84
1987 71.04
1988 71.21
1989 71.42
1990 71.66
1991 71.83
1992 71.99
1993 72.12
1994 72.22
1995 72.36
1996 72.53
1997 72.71
1998 72.83
1999 72.94
2000 73.12
2001 73.28
2002 73.38
2003 73.54
2004 73.74
2005 73.91
2006 74.06
2007 74.15
2008 74.25
2009 74.34
2010 74.46
2011 74.58
2012 74.72
2013 74.9
2014 75.1
2015 75.37
2016 75.61
2017 75.76
2018 75.91