Year Years
1800 29
1801 29
1802 29
1803 29
1804 29
1805 29
1806 29
1807 29
1808 29
1809 29
1810 29
1811 29
1812 29
1813 29
1814 29
1815 29
1816 29
1817 29
1818 29
1819 29
1820 29
1821 29
1822 29
1823 29
1824 29
1825 29
1826 29
1827 29
1828 29
1829 29
1830 29
1831 29
1832 29
1833 29
1834 29
1835 29
1836 29
1837 29
1838 29
1839 29
1840 29
1841 29
1842 29
1843 29
1844 29
1845 29
1846 29
1847 29
1848 29
1849 29
1850 29
1851 29
1852 29
1853 29
1854 29
1855 29
1856 29
1857 29
1858 29
1859 29
1860 29
1861 29
1862 29
1863 29
1864 29
1865 29
1866 29
1867 29
1868 29
1869 29
1870 29
1871 28.99
1872 28.98
1873 28.97
1874 28.96
1875 28.95
1876 28.94
1877 28.93
1878 28.92
1879 28.91
1880 28.9
1881 28.89
1882 28.88
1883 28.87
1884 28.86
1885 28.85
1886 28.84
1887 28.83
1888 28.82
1889 28.81
1890 28.8
1891 28.79
1892 28.78
1893 28.77
1894 28.76
1895 28.75
1896 28.74
1897 28.73
1898 28.72
1899 28.71
1900 28.7
1901 28.69
1902 28.68
1903 28.67
1904 28.67
1905 28.66
1906 28.65
1907 28.64
1908 28.63
1909 28.62
1910 28.61
1911 28.6
1912 28.59
1913 28.58
1914 28.57
1915 28.56
1916 28.55
1917 28.54
1918 18.5
1919 28.52
1920 28.51
1921 28.5
1922 28.49
1923 28.48
1924 28.47
1925 28.46
1926 28.45
1927 28.44
1928 28.43
1929 28.42
1930 28.41
1931 28.4
1932 28.39
1933 28.38
1934 28.37
1935 28.36
1936 28.35
1937 28.34
1938 28.33
1939 28.32
1940 28.31
1941 28.3
1942 28.29
1943 29.17
1944 30.05
1945 30.92
1946 31.79
1947 32.66
1948 33.54
1949 34.41
1950 35.28
1951 35.59
1952 36.22
1953 36.84
1954 37.45
1955 38.04
1956 38.63
1957 39.21
1958 39.76
1959 40.32
1960 40.88
1961 41.43
1962 41.98
1963 42.51
1964 43.04
1965 43.56
1966 44.04
1967 44.47
1968 44.88
1969 45.26
1970 45.6
1971 45.97
1972 46.39
1973 47.06
1974 47.76
1975 48.26
1976 48.67
1977 49.01
1978 49.35
1979 49.81
1980 50.35
1981 50.97
1982 51.43
1983 51.79
1984 52.12
1985 52.46
1986 52.76
1987 53.26
1988 53.66
1989 53.79
1990 54.06
1991 54.21
1992 54.55
1993 54.18
1994 54.6
1995 55.12
1996 55.47
1997 55.7
1998 56.05
1999 56.38
2000 56.8
2001 57.13
2002 57.46
2003 57.61
2004 56.61
2005 58.03
2006 58.35
2007 58.87
2008 59.3
2009 60.04
2010 32.11
2011 60.54
2012 61.63
2013 62.51
2014 63.3
2015 63.88
2016 64
2017 64.27
2018 64.52