Year Years
1800 31.6
1801 31.6
1802 31.6
1803 31.6
1804 31.6
1805 31.6
1806 31.6
1807 31.6
1808 31.6
1809 31.6
1810 31.6
1811 31.6
1812 31.6
1813 31.6
1814 31.6
1815 31.6
1816 31.6
1817 31.6
1818 31.6
1819 31.6
1820 31.6
1821 31.6
1822 31.6
1823 31.6
1824 31.6
1825 31.6
1826 31.6
1827 31.6
1828 31.6
1829 31.6
1830 31.6
1831 31.6
1832 31.6
1833 31.6
1834 31.6
1835 31.6
1836 31.6
1837 31.6
1838 31.6
1839 31.6
1840 31.6
1841 31.6
1842 31.6
1843 31.6
1844 31.6
1845 31.6
1846 31.6
1847 31.6
1848 31.6
1849 31.6
1850 31.6
1851 31.6
1852 31.6
1853 31.6
1854 31.6
1855 31.6
1856 31.6
1857 31.6
1858 31.6
1859 31.6
1860 31.6
1861 31.6
1862 31.6
1863 31.6
1864 31.6
1865 31.6
1866 31.6
1867 31.6
1868 31.6
1869 31.6
1870 31.6
1871 31.65
1872 31.69
1873 31.74
1874 31.78
1875 31.83
1876 31.88
1877 31.92
1878 31.97
1879 32.02
1880 32.06
1881 32.11
1882 32.15
1883 32.2
1884 32.25
1885 32.29
1886 32.34
1887 32.38
1888 32.43
1889 32.48
1890 32.52
1891 32.57
1892 32.62
1893 32.66
1894 32.71
1895 32.75
1896 32.8
1897 32.85
1898 32.89
1899 32.94
1900 32.98
1901 33.03
1902 33.08
1903 33.12
1904 33.17
1905 33.21
1906 33.26
1907 33.31
1908 33.35
1909 33.4
1910 33.45
1911 33.49
1912 33.54
1913 33.58
1914 33.63
1915 33.68
1916 33.72
1917 33.77
1918 9.68
1919 33.86
1920 33.91
1921 33.95
1922 34
1923 34.05
1924 34.09
1925 34.14
1926 34.18
1927 34.23
1928 34.28
1929 34.32
1930 34.37
1931 34.41
1932 34.46
1933 34.51
1934 34.55
1935 34.6
1936 34.65
1937 34.69
1938 34.74
1939 34.78
1940 34.83
1941 35.62
1942 36.41
1943 37.2
1944 38.01
1945 38.8
1946 39.61
1947 40.4
1948 41.2
1949 42.02
1950 42.82
1951 43.09
1952 43.56
1953 44
1954 44.42
1955 44.82
1956 45.19
1957 45.54
1958 45.87
1959 46.19
1960 46.5
1961 46.8
1962 47.11
1963 47.43
1964 47.76
1965 48.12
1966 48.51
1967 48.94
1968 49.39
1969 49.86
1970 50.33
1971 50.6
1972 50.8
1973 51.1
1974 51.45
1975 51.62
1976 51.82
1977 52.04
1978 52.2
1979 52.46
1980 52.64
1981 52.81
1982 53.09
1983 53.43
1984 53.94
1985 54.19
1986 54.29
1987 54.23
1988 54.19
1989 54.06
1990 53.82
1991 53.62
1992 53.58
1993 53.48
1994 53.2
1995 53.14
1996 51.13
1997 52.47
1998 52.63
1999 53.06
2000 53.37
2001 53.6
2002 53.76
2003 54.03
2004 54.87
2005 55.36
2006 55.89
2007 56.15
2008 56.48
2009 56.9
2010 57.53
2011 58.03
2012 58.53
2013 59.33
2014 60.12
2015 60.93
2016 61.58
2017 62
2018 62.42