Year Years
1800 35.5
1801 35.5
1802 35.5
1803 35.5
1804 35.5
1805 35.5
1806 35.5
1807 35.5
1808 35.5
1809 35.5
1810 35.5
1811 35.5
1812 35.5
1813 35.5
1814 35.5
1815 35.5
1816 35.5
1817 35.5
1818 35.5
1819 35.5
1820 35.5
1821 35.5
1822 35.5
1823 35.5
1824 35.5
1825 35.5
1826 35.5
1827 35.5
1828 35.5
1829 35.5
1830 35.5
1831 35.5
1832 35.5
1833 35.5
1834 35.5
1835 35.5
1836 35.5
1837 35.5
1838 35.5
1839 35.5
1840 35.5
1841 35.5
1842 35.5
1843 35.5
1844 35.5
1845 35.5
1846 35.5
1847 35.5
1848 35.5
1849 35.5
1850 35.5
1851 35.5
1852 35.5
1853 35.5
1854 35.5
1855 35.5
1856 35.5
1857 35.5
1858 35.5
1859 35.5
1860 35.5
1861 35.5
1862 35.5
1863 35.5
1864 35.5
1865 35.5
1866 35.5
1867 35.5
1868 35.5
1869 35.5
1870 35.5
1871 35.51
1872 35.52
1873 35.54
1874 35.55
1875 35.56
1876 35.57
1877 35.58
1878 35.6
1879 35.61
1880 35.62
1881 35.63
1882 35.64
1883 35.65
1884 35.67
1885 35.68
1886 35.69
1887 35.7
1888 35.71
1889 35.73
1890 35.74
1891 35.75
1892 35.76
1893 35.77
1894 35.79
1895 35.8
1896 35.81
1897 35.82
1898 35.83
1899 35.84
1900 35.86
1901 35.87
1902 35.88
1903 35.89
1904 35.9
1905 35.92
1906 35.93
1907 35.94
1908 35.95
1909 35.96
1910 35.98
1911 35.99
1912 36
1913 36.01
1914 25.37
1915 16.24
1916 21.32
1917 20.31
1918 10.06
1919 36.08
1920 36.09
1921 36.88
1922 37.65
1923 38.44
1924 39.22
1925 40
1926 40.79
1927 41.57
1928 42.36
1929 43.14
1930 43.93
1931 44.71
1932 45.5
1933 46.29
1934 47.07
1935 47.86
1936 48.64
1937 49.44
1938 50.23
1939 51.01
1940 51.81
1941 45.13
1942 42.83
1943 41.3
1944 39.79
1945 44.43
1946 52.3
1947 56.62
1948 58.08
1949 58.92
1950 59.74
1951 60
1952 60.49
1953 61
1954 61.52
1955 62.05
1956 62.58
1957 63.14
1958 63.69
1959 64.26
1960 64.83
1961 65.4
1962 65.97
1963 66.54
1964 67.1
1965 67.65
1966 68.16
1967 68.67
1968 69.15
1969 69.59
1970 70.01
1971 70.09
1972 70.44
1973 70.76
1974 70.98
1975 71.14
1976 71.3
1977 71.42
1978 71.53
1979 71.61
1980 71.7
1981 71.75
1982 71.83
1983 71.89
1984 71.94
1985 72.08
1986 72.21
1987 72.34
1988 72.46
1989 72.53
1990 72.6
1991 71.69
1992 71.92
1993 72.3
1994 72.06
1995 70.73
1996 71.89
1997 72.05
1998 71.45
1999 70.96
2000 72.16
2001 72.39
2002 72.5
2003 72.69
2004 72.91
2005 73.22
2006 73.55
2007 73.89
2008 74.23
2009 74.45
2010 74.65
2011 74.85
2012 75.1
2013 75.34
2014 75.53
2015 75.74
2016 75.91
2017 76.04
2018 76.17