Year Years
1800 36.6
1801 36.6
1802 36.6
1803 36.6
1804 36.6
1805 36.6
1806 36.6
1807 36.6
1808 36.6
1809 36.6
1810 36.6
1811 36.6
1812 36.6
1813 36.6
1814 36.6
1815 36.6
1816 36.6
1817 36.6
1818 36.6
1819 36.6
1820 36.6
1821 36.6
1822 36.6
1823 36.6
1824 36.6
1825 36.6
1826 36.6
1827 36.6
1828 36.6
1829 36.6
1830 36.6
1831 36.6
1832 36.6
1833 36.6
1834 36.6
1835 36.6
1836 36.6
1837 36.6
1838 36.6
1839 36.6
1840 36.6
1841 36.6
1842 36.6
1843 36.6
1844 36.6
1845 36.6
1846 36.6
1847 36.6
1848 36.6
1849 36.6
1850 36.6
1851 36.6
1852 36.6
1853 36.6
1854 36.6
1855 36.6
1856 36.6
1857 36.6
1858 36.6
1859 36.6
1860 36.6
1861 36.6
1862 36.6
1863 36.6
1864 36.6
1865 36.6
1866 36.6
1867 36.6
1868 36.6
1869 36.6
1870 36.6
1871 36.59
1872 36.58
1873 36.57
1874 36.56
1875 36.55
1876 36.54
1877 36.53
1878 36.52
1879 36.51
1880 36.5
1881 36.5
1882 36.49
1883 36.48
1884 36.47
1885 36.46
1886 36.45
1887 36.44
1888 36.43
1889 36.42
1890 36.41
1891 36.4
1892 36.39
1893 36.38
1894 36.37
1895 36.36
1896 36.35
1897 36.34
1898 36.33
1899 36.32
1900 36.31
1901 36.7
1902 37.09
1903 37.47
1904 37.85
1905 38.24
1906 38.62
1907 39.01
1908 39.39
1909 39.77
1910 40.16
1911 40.54
1912 40.93
1913 41.31
1914 40.09
1915 34.59
1916 34.58
1917 32.6
1918 28.64
1919 30.6
1920 27.68
1921 30.93
1922 31.81
1923 40.58
1924 43.04
1925 42.14
1926 45.28
1927 44.38
1928 45.95
1929 44.06
1930 44
1931 44.97
1932 36.35
1933 8.9
1934 39.09
1935 48.76
1936 49.44
1937 48.19
1938 49.41
1939 49.2
1940 48.99
1941 24.49
1942 19.18
1943 17.9
1944 28.39
1945 34.86
1946 54.21
1947 44.34
1948 56.72
1949 59.45
1950 61.35
1951 60.99
1952 61.7
1953 62.37
1954 63.14
1955 64.93
1956 65.79
1957 65.82
1958 67.47
1959 67.82
1960 69.39
1961 69.65
1962 69.07
1963 69.66
1964 70.42
1965 69.86
1966 70.1
1967 69.69
1968 69.76
1969 69.14
1970 69.02
1971 69.16
1972 69.21
1973 69.41
1974 69.4
1975 69.13
1976 69.23
1977 68.96
1978 68.81
1979 68.62
1980 68.63
1981 68.71
1982 68.95
1983 69.15
1984 68.93
1985 69.42
1986 70.7
1987 70.62
1988 70.6
1989 70.24
1990 69.88
1991 69.31
1992 68.76
1993 68.24
1994 67.56
1995 66.62
1996 66.8
1997 67.37
1998 68.12
1999 67.75
2000 67.44
2001 67.66
2002 67.75
2003 67.76
2004 67.61
2005 67.25
2006 67.92
2007 67.73
2008 67.97
2009 69.58
2010 70.41
2011 71.1
2012 71.11
2013 71.26
2014 71.72
2015 71.93
2016 72
2017 72.15
2018 72.29