Year Years
1800 32.6
1801 32.6
1802 32.6
1803 32.6
1804 32.6
1805 32.6
1806 32.6
1807 32.6
1808 32.6
1809 32.6
1810 32.6
1811 32.6
1812 32.6
1813 32.6
1814 32.6
1815 32.6
1816 32.6
1817 32.6
1818 32.6
1819 32.6
1820 32.6
1821 32.6
1822 32.6
1823 32.6
1824 32.6
1825 32.6
1826 32.6
1827 32.6
1828 32.6
1829 32.6
1830 32.6
1831 32.6
1832 32.6
1833 32.6
1834 32.6
1835 32.6
1836 32.6
1837 32.6
1838 32.6
1839 32.6
1840 32.6
1841 32.6
1842 32.6
1843 32.6
1844 32.6
1845 32.6
1846 32.6
1847 32.6
1848 32.6
1849 32.6
1850 32.6
1851 32.6
1852 32.6
1853 32.6
1854 32.6
1855 32.6
1856 32.6
1857 32.6
1858 32.6
1859 32.6
1860 32.6
1861 32.6
1862 32.6
1863 32.6
1864 32.6
1865 32.6
1866 32.6
1867 32.6
1868 32.6
1869 32.6
1870 32.6
1871 32.6
1872 32.61
1873 32.61
1874 32.62
1875 32.62
1876 32.62
1877 32.63
1878 32.63
1879 32.63
1880 32.64
1881 32.64
1882 32.65
1883 32.65
1884 32.65
1885 32.66
1886 32.66
1887 32.67
1888 32.67
1889 32.67
1890 32.68
1891 32.68
1892 32.69
1893 32.69
1894 32.69
1895 32.7
1896 32.7
1897 32.7
1898 32.71
1899 32.71
1900 32.72
1901 32.72
1902 32.8
1903 34.15
1904 35.02
1905 32.66
1906 27.15
1907 30.3
1908 30.76
1909 30.08
1910 33.01
1911 27.43
1912 29.14
1913 32.11
1914 29.35
1915 34.62
1916 32.94
1917 34.55
1918 28.36
1919 25.6
1920 31.28
1921 32.19
1922 36.26
1923 33.44
1924 38.1
1925 39.92
1926 38.67
1927 41.82
1928 37.9
1929 37.68
1930 38.46
1931 42.46
1932 44.48
1933 43.58
1934 41.49
1935 27.97
1936 42.84
1937 42.98
1938 43.86
1939 42.99
1940 44.39
1941 47.46
1942 47.74
1943 44.14
1944 44.15
1945 43.27
1946 46.21
1947 53.79
1948 53.52
1949 53.26
1950 52.98
1951 53.55
1952 54.64
1953 55.61
1954 56.51
1955 57.29
1956 57.99
1957 58.59
1958 59.12
1959 59.59
1960 60.02
1961 60.43
1962 60.85
1963 61.29
1964 61.77
1965 62.29
1966 62.83
1967 63.37
1968 63.9
1969 64.4
1970 64.87
1971 64.72
1972 64.73
1973 64.71
1974 64.44
1975 64.88
1976 65.48
1977 66.33
1978 67.35
1979 68.14
1980 68.89
1981 69.55
1982 69.68
1983 69.79
1984 69.78
1985 70.35
1986 70.79
1987 70.8
1988 71.12
1989 71.66
1990 71.58
1991 71.63
1992 72.19
1993 72.94
1994 73.02
1995 72.22
1996 72.11
1997 72.13
1998 72.22
1999 72.66
2000 72.75
2001 73.28
2002 73.53
2003 74.11
2004 69.58
2005 74.08
2006 74.39
2007 74.73
2008 74.05
2009 73.93
2010 74.42
2011 75.96
2012 76.3
2013 76.6
2014 76.87
2015 77.17
2016 77.4
2017 77.61
2018 77.82