Year Years
1800 25.8
1801 25.8
1802 25.8
1803 25.8
1804 25.8
1805 25.8
1806 25.8
1807 25.8
1808 25.8
1809 25.8
1810 25.8
1811 25.8
1812 23.3
1813 25.8
1814 25.8
1815 25.8
1816 25.8
1817 25.8
1818 25.8
1819 25.8
1820 25.8
1821 25.8
1822 25.8
1823 25.8
1824 25.8
1825 25.8
1826 25.8
1827 25.8
1828 25.8
1829 25.8
1830 25.8
1831 25.8
1832 25.8
1833 25.8
1834 25.8
1835 25.8
1836 25.8
1837 25.8
1838 25.8
1839 25.8
1840 25.8
1841 25.8
1842 25.8
1843 25.8
1844 25.8
1845 25.8
1846 25.8
1847 25.8
1848 25.8
1849 25.8
1850 25.8
1851 25.8
1852 25.8
1853 25.8
1854 25.8
1855 25.8
1856 25.8
1857 25.8
1858 25.8
1859 25.8
1860 25.8
1861 25.8
1862 25.8
1863 25.8
1864 25.8
1865 25.8
1866 25.8
1867 25.8
1868 25.8
1869 25.8
1870 25.8
1871 25.82
1872 25.83
1873 25.85
1874 25.87
1875 25.88
1876 25.9
1877 26.05
1878 26.2
1879 26.34
1880 26.49
1881 26.64
1882 26.79
1883 26.94
1884 27.08
1885 27.23
1886 27.38
1887 27
1888 26.63
1889 26.25
1890 25.87
1891 25.49
1892 23.9
1893 24.73
1894 24.35
1895 23.97
1896 23.59
1897 23.4
1898 23.21
1899 23.02
1900 21.47
1901 22.65
1902 22.46
1903 22.27
1904 20.73
1905 20.55
1906 20.36
1907 18.2
1908 22.36
1909 22.69
1910 23.02
1911 23.35
1912 23.69
1913 24.02
1914 24.36
1915 24.69
1916 25.02
1917 25.36
1918 8.47
1919 26.03
1920 26.37
1921 26.7
1922 27.04
1923 27.38
1924 27.72
1925 28.06
1926 28.39
1927 28.79
1928 29.18
1929 29.57
1930 29.96
1931 30.35
1932 30.75
1933 31.14
1934 31.54
1935 31.93
1936 32.33
1937 32.72
1938 33.12
1939 33.52
1940 33.91
1941 34.31
1942 34.71
1943 35.11
1944 35.51
1945 35.9
1946 36.3
1947 11.26
1948 33.1
1949 37.51
1950 37.91
1951 38.56
1952 39.85
1953 41.11
1954 42.34
1955 43.54
1956 44.72
1957 45.87
1958 46.99
1959 48.07
1960 49.12
1961 50.12
1962 51.09
1963 51.99
1964 52.85
1965 53.64
1966 54.39
1967 55.08
1968 55.74
1969 56.36
1970 56.95
1971 52.27
1972 57.71
1973 58.07
1974 58.2
1975 58.67
1976 58.98
1977 59.27
1978 59.68
1979 59.99
1980 60.32
1981 60.65
1982 61.01
1983 61.33
1984 61.63
1985 61.75
1986 61.98
1987 62.01
1988 62.09
1989 62.27
1990 62.45
1991 62.53
1992 62.42
1993 62.3
1994 62.16
1995 61.95
1996 62.1
1997 62.08
1998 62.29
1999 62.45
2000 62.63
2001 62.78
2002 62.94
2003 63.1
2004 63.37
2005 62.56
2006 64.05
2007 64.39
2008 64.68
2009 65.01
2010 65.33
2011 65.77
2012 66.12
2013 66.51
2014 66.88
2015 67.26
2016 67.66
2017 67.81
2018 67.96