Year Years
1800 32.9
1801 32.9
1802 32.9
1803 32.9
1804 32.9
1805 32.9
1806 32.9
1807 32.9
1808 32.9
1809 32.9
1810 32.9
1811 32.9
1812 32.9
1813 32.9
1814 32.9
1815 32.9
1816 32.9
1817 32.9
1818 32.9
1819 32.9
1820 32.9
1821 32.9
1822 32.9
1823 32.9
1824 32.9
1825 32.9
1826 32.9
1827 32.9
1828 32.9
1829 32.9
1830 32.9
1831 32.9
1832 32.9
1833 32.9
1834 32.9
1835 32.9
1836 32.9
1837 32.9
1838 32.9
1839 33.88
1840 34.87
1841 35.85
1842 36.83
1843 37.82
1844 38.8
1845 38.8
1846 38.8
1847 38.8
1848 38.8
1849 38.8
1850 38.8
1851 38.8
1852 38.8
1853 38.8
1854 38.8
1855 38.8
1856 38.8
1857 38.8
1858 38.8
1859 38.8
1860 38.8
1861 38.8
1862 38.8
1863 38.8
1864 38.8
1865 38.8
1866 38.8
1867 38.8
1868 38.8
1869 38.8
1870 38.8
1871 38.8
1872 38.8
1873 38.81
1874 38.81
1875 38.81
1876 38.81
1877 38.82
1878 38.82
1879 38.82
1880 38.82
1881 38.83
1882 38.83
1883 38.83
1884 38.83
1885 38.84
1886 38.84
1887 38.84
1888 38.84
1889 38.85
1890 38.85
1891 38.85
1892 38.85
1893 38.85
1894 38.86
1895 38.86
1896 38.86
1897 38.86
1898 38.87
1899 38.87
1900 38.87
1901 38.87
1902 38.88
1903 38.88
1904 38.88
1905 38.88
1906 38.89
1907 38.89
1908 38.89
1909 38.89
1910 38.9
1911 38.9
1912 38.9
1913 38.9
1914 38.9
1915 38.91
1916 38.91
1917 38.91
1918 25.23
1919 38.92
1920 38.92
1921 38.92
1922 39.62
1923 40.31
1924 41.01
1925 41.7
1926 42.4
1927 43.09
1928 43.79
1929 44.48
1930 45.18
1931 45.87
1932 46.47
1933 47.05
1934 47.65
1935 48.24
1936 48.83
1937 49.42
1938 50.02
1939 50.6
1940 51.2
1941 51.8
1942 52.38
1943 52.98
1944 53.57
1945 54.16
1946 54.75
1947 55.36
1948 55.97
1949 56.56
1950 57.17
1951 57.4
1952 57.88
1953 58.41
1954 58.97
1955 59.59
1956 60.24
1957 60.92
1958 61.62
1959 62.31
1960 62.98
1961 63.57
1962 64.08
1963 64.5
1964 64.79
1965 65
1966 65.12
1967 65.21
1968 65.28
1969 65.37
1970 65.48
1971 65.58
1972 65.74
1973 65.96
1974 66.26
1975 66.51
1976 66.8
1977 67.13
1978 67.47
1979 67.74
1980 68.12
1981 68.38
1982 68.64
1983 68.69
1984 68.81
1985 68.96
1986 69.08
1987 69.13
1988 69.16
1989 69.17
1990 69.07
1991 69.18
1992 69.08
1993 69.18
1994 69.16
1995 69.33
1996 69.32
1997 69.44
1998 69.57
1999 69.34
2000 69.51
2001 69.76
2002 70.02
2003 70.49
2004 71.08
2005 71.34
2006 71.65
2007 72.07
2008 72.31
2009 72.5
2010 72.56
2011 72.66
2012 72.79
2013 72.9
2014 72.99
2015 73.07
2016 73.15
2017 73.26
2018 73.37