Year Years
1800 26.9
1801 26.9
1802 26.9
1803 26.9
1804 26.9
1805 26.9
1806 26.9
1807 26.9
1808 26.9
1809 26.9
1810 26.9
1811 26.9
1812 26.9
1813 26.9
1814 26.9
1815 26.9
1816 26.9
1817 26.9
1818 26.9
1819 26.9
1820 26.9
1821 26.9
1822 26.9
1823 26.9
1824 26.9
1825 26.9
1826 26.9
1827 26.9
1828 26.9
1829 26.9
1830 26.9
1831 26.9
1832 26.9
1833 26.9
1834 26.9
1835 26.9
1836 26.9
1837 26.9
1838 26.9
1839 26.9
1840 26.9
1841 26.9
1842 26.9
1843 26.9
1844 26.9
1845 26.9
1846 26.9
1847 26.9
1848 26.9
1849 26.9
1850 26.9
1851 26.9
1852 26.9
1853 26.9
1854 26.9
1855 26.9
1856 26.9
1857 26.9
1858 26.9
1859 26.9
1860 26.9
1861 26.9
1862 26.9
1863 26.9
1864 26.9
1865 26.9
1866 26.9
1867 26.9
1868 26.9
1869 26.9
1870 26.9
1871 26.9
1872 26.91
1873 26.91
1874 26.91
1875 26.92
1876 26.92
1877 26.92
1878 26.93
1879 26.93
1880 26.93
1881 26.94
1882 26.94
1883 26.94
1884 26.95
1885 26.95
1886 26.95
1887 26.96
1888 26.96
1889 26.96
1890 26.97
1891 25.77
1892 24.56
1893 23.36
1894 26.7
1895 29.61
1896 28.89
1897 26.33
1898 27.13
1899 25.07
1900 27.68
1901 26.75
1902 28.48
1903 28.8
1904 29.21
1905 26.92
1906 28.01
1907 28.1
1908 28.86
1909 29.35
1910 27.55
1911 27.98
1912 28.43
1913 28.87
1914 29.3
1915 29.74
1916 30.18
1917 30.62
1918 18.3
1919 31.49
1920 31.94
1921 32.38
1922 32.81
1923 33.72
1924 33.02
1925 32.32
1926 34.44
1927 40.59
1928 34.75
1929 35.66
1930 36.47
1931 37.99
1932 38.7
1933 37.6
1934 38.51
1935 40.73
1936 38.62
1937 37.11
1938 39.74
1939 45.89
1940 39.54
1941 42.98
1942 40.16
1943 43.19
1944 43.6
1945 44.62
1946 45.23
1947 46.75
1948 48.77
1949 46.25
1950 49.05
1951 49.62
1952 50.73
1953 51.78
1954 52.8
1955 53.76
1956 54.66
1957 55.52
1958 56.32
1959 57.05
1960 57.73
1961 58.33
1962 58.87
1963 59.35
1964 59.78
1965 60.16
1966 60.53
1967 60.9
1968 61.29
1969 61.7
1970 62.14
1971 63.04
1972 63.36
1973 63.6
1974 64.18
1975 64.66
1976 65.02
1977 65.35
1978 66.18
1979 66.36
1980 66.72
1981 67.22
1982 67.84
1983 68.41
1984 68.89
1985 69.07
1986 69.84
1987 70.31
1988 70.64
1989 71.05
1990 71.55
1991 71.93
1992 72.13
1993 72.34
1994 72.65
1995 72.87
1996 73.24
1997 73.48
1998 73.72
1999 74.14
2000 74.61
2001 74.87
2002 74.89
2003 74.93
2004 75.22
2005 75.21
2006 75.46
2007 75.66
2008 75.46
2009 75.37
2010 75.47
2011 75.75
2012 75.9
2013 75.82
2014 75.93
2015 76.21
2016 76.41
2017 76.59
2018 76.78