Year Years
1800 25.5
1801 25.5
1802 25.5
1803 25.5
1804 25.5
1805 25.5
1806 25.5
1807 25.5
1808 25.5
1809 25.5
1810 25.5
1811 25.5
1812 25.5
1813 25.5
1814 25.5
1815 25.5
1816 25.5
1817 25.5
1818 25.5
1819 25.5
1820 25.5
1821 25.5
1822 25.5
1823 25.5
1824 25.5
1825 25.5
1826 25.5
1827 25.5
1828 25.5
1829 25.5
1830 25.5
1831 25.5
1832 25.5
1833 25.5
1834 25.5
1835 25.5
1836 25.5
1837 25.5
1838 25.5
1839 25.5
1840 25.5
1841 25.5
1842 25.5
1843 25.5
1844 25.5
1845 25.5
1846 25.5
1847 25.5
1848 25.5
1849 25.5
1850 25.5
1851 25.5
1852 25.5
1853 25.5
1854 25.5
1855 25.5
1856 25.5
1857 25.5
1858 25.5
1859 25.5
1860 25.5
1861 25.5
1862 25.5
1863 25.5
1864 25.5
1865 25.5
1866 25.5
1867 25.5
1868 25.5
1869 25.5
1870 25.5
1871 25.53
1872 25.56
1873 25.58
1874 25.61
1875 25.64
1876 25.67
1877 25.7
1878 25.72
1879 25.75
1880 25.78
1881 25.81
1882 25.83
1883 25.86
1884 25.89
1885 25.92
1886 25.95
1887 25.97
1888 26
1889 26.03
1890 26.06
1891 26.09
1892 26.11
1893 26.14
1894 26.17
1895 26.2
1896 26.23
1897 26.25
1898 26.28
1899 26.31
1900 26.34
1901 26.36
1902 26.39
1903 26.42
1904 26.45
1905 26.48
1906 26.5
1907 26.53
1908 26.56
1909 26.59
1910 26.62
1911 26.64
1912 26.67
1913 26.7
1914 26.73
1915 26.76
1916 26.78
1917 26.81
1918 6.33
1919 26.87
1920 26.9
1921 26.92
1922 26.95
1923 26.64
1924 26.34
1925 26.03
1926 25.73
1927 25.41
1928 25.7
1929 25.99
1930 26.28
1931 26.56
1932 26.86
1933 27.14
1934 27.44
1935 27.72
1936 28.02
1937 28.3
1938 28.67
1939 29.03
1940 29.38
1941 29.74
1942 30.1
1943 30.46
1944 30.83
1945 31.19
1946 33.98
1947 36.79
1948 39.59
1949 42.4
1950 45.23
1951 45.44
1952 45.84
1953 46.32
1954 46.83
1955 47.4
1956 48.02
1957 48.69
1958 49.41
1959 50.15
1960 50.91
1961 51.68
1962 52.44
1963 53.16
1964 53.86
1965 54.55
1966 55.21
1967 55.87
1968 56.55
1969 57.23
1970 57.93
1971 58.27
1972 58.67
1973 59.06
1974 59.46
1975 59.82
1976 60.18
1977 60.57
1978 60.98
1979 61.34
1980 61.67
1981 61.94
1982 62.15
1983 62.42
1984 62.51
1985 62.61
1986 62.64
1987 62.4
1988 62.42
1989 61.9
1990 61.44
1991 60.74
1992 59.86
1993 58.96
1994 58.05
1995 57.26
1996 56.55
1997 55.85
1998 55.29
1999 55.27
2000 55.21
2001 55.46
2002 55.67
2003 56
2004 56.56
2005 57.43
2006 58.48
2007 59.62
2008 60.65
2009 61.68
2010 62.76
2011 63.76
2012 64.6
2013 65.2
2014 65.78
2015 66.35
2016 66.88
2017 67.13
2018 67.35