Year Years
1800 30.9
1801 30.9
1802 30.9
1803 30.9
1804 30.9
1805 30.9
1806 30.9
1807 30.9
1808 30.9
1809 30.9
1810 30.9
1811 30.9
1812 30.9
1813 30.9
1814 30.9
1815 30.9
1816 30.9
1817 30.9
1818 30.9
1819 30.9
1820 30.9
1821 30.9
1822 30.9
1823 30.9
1824 30.9
1825 30.9
1826 30.9
1827 30.9
1828 30.9
1829 30.9
1830 30.9
1831 30.9
1832 30.9
1833 30.9
1834 30.9
1835 30.9
1836 30.9
1837 30.9
1838 30.9
1839 30.9
1840 30.9
1841 30.9
1842 30.9
1843 30.9
1844 30.9
1845 30.9
1846 30.9
1847 30.9
1848 30.9
1849 30.9
1850 30.9
1851 30.9
1852 30.9
1853 30.9
1854 30.9
1855 30.9
1856 30.9
1857 30.9
1858 30.9
1859 30.9
1860 30.9
1861 30.9
1862 30.9
1863 30.9
1864 30.9
1865 30.9
1866 30.9
1867 30.9
1868 30.9
1869 30.9
1870 30.9
1871 30.91
1872 30.92
1873 30.93
1874 30.94
1875 30.96
1876 30.97
1877 30.98
1878 30.99
1879 31
1880 31.01
1881 31.02
1882 31.03
1883 31.05
1884 31.06
1885 31.07
1886 31.08
1887 31.09
1888 31.1
1889 31.11
1890 31.12
1891 31.13
1892 31.15
1893 31.16
1894 31.17
1895 31.18
1896 31.19
1897 31.2
1898 31.21
1899 31.22
1900 31.24
1901 31.25
1902 12.85
1903 20.24
1904 31.28
1905 31.29
1906 31.3
1907 31.31
1908 31.32
1909 31.34
1910 31.35
1911 31.36
1912 31.37
1913 31.38
1914 31.39
1915 31.4
1916 31.41
1917 31.43
1918 26.04
1919 31.45
1920 31.46
1921 31.47
1922 31.48
1923 31.49
1924 31.5
1925 31.51
1926 32.24
1927 32.97
1928 33.69
1929 34.42
1930 35.15
1931 35.87
1932 36.6
1933 37.33
1934 38.06
1935 38.79
1936 39.52
1937 40.25
1938 40.98
1939 42.26
1940 43.54
1941 42.05
1942 35.71
1943 38.08
1944 33.37
1945 30.71
1946 42.13
1947 45.67
1948 49.22
1949 52.77
1950 56.32
1951 56.52
1952 56.9
1953 57.28
1954 57.64
1955 58.01
1956 58.36
1957 58.72
1958 59.07
1959 59.41
1960 59.75
1961 60.08
1962 60.43
1963 60.76
1964 61.08
1965 61.41
1966 61.74
1967 62.07
1968 62.41
1969 62.73
1970 63.03
1971 63.32
1972 63.29
1973 63.48
1974 63.65
1975 63.85
1976 63.67
1977 64.24
1978 64.42
1979 64.72
1980 64.88
1981 65.03
1982 65.15
1983 65.42
1984 65.46
1985 65.61
1986 65.79
1987 65.95
1988 66.41
1989 66.9
1990 67.18
1991 67.34
1992 67.73
1993 67.9
1994 68.08
1995 68.16
1996 68.34
1997 68.41
1998 68.38
1999 68.35
2000 68.24
2001 68.25
2002 68.23
2003 68.21
2004 68.21
2005 68.33
2006 68.32
2007 68.55
2008 68.67
2009 68.82
2010 69.03
2011 69.17
2012 69.33
2013 69.4
2014 69.82
2015 70.06
2016 70.26
2017 70.4
2018 70.55