Year Total
1800 4.9
1801 4.89
1802 4.88
1803 4.87
1804 4.86
1805 4.84
1806 4.83
1807 4.82
1808 4.81
1809 4.8
1810 4.79
1811 4.78
1812 4.77
1813 4.76
1814 4.74
1815 4.73
1816 4.72
1817 4.71
1818 4.7
1819 4.69
1820 4.68
1821 4.67
1822 4.66
1823 4.64
1824 4.63
1825 4.62
1826 4.61
1827 4.6
1828 4.59
1829 4.58
1830 4.57
1831 4.56
1832 4.54
1833 4.53
1834 4.52
1835 4.51
1836 4.5
1837 4.49
1838 4.48
1839 4.47
1840 4.46
1841 4.44
1842 4.43
1843 4.42
1844 4.41
1845 4.4
1846 4.39
1847 4.38
1848 4.37
1849 4.36
1850 4.34
1851 4.33
1852 4.32
1853 4.31
1854 4.3
1855 4.29
1856 4.28
1857 4.27
1858 4.26
1859 4.24
1860 4.23
1861 4.22
1862 4.21
1863 4.2
1864 4.19
1865 4.18
1866 4.22
1867 4.27
1868 4.31
1869 4.36
1870 4.4
1871 4.45
1872 4.49
1873 4.54
1874 4.58
1875 4.63
1876 4.61
1877 4.6
1878 4.58
1879 4.57
1880 4.55
1881 4.54
1882 4.52
1883 4.51
1884 4.49
1885 4.48
1886 4.51
1887 4.54
1888 4.57
1889 4.6
1890 4.63
1891 4.65
1892 4.68
1893 4.71
1894 4.74
1895 4.77
1896 4.77
1897 4.77
1898 4.77
1899 4.77
1900 4.77
1901 4.77
1902 4.77
1903 4.77
1904 4.77
1905 4.77
1906 4.78
1907 4.79
1908 4.8
1909 4.8
1910 4.81
1911 4.82
1912 4.83
1913 4.83
1914 4.84
1915 4.85
1916 4.91
1917 4.97
1918 5.04
1919 5.1
1920 5.16
1921 5.22
1922 5.28
1923 5.35
1924 5.41
1925 5.47
1926 5.51
1927 5.54
1928 5.58
1929 5.62
1930 5.65
1931 5.69
1932 5.73
1933 5.77
1934 5.8
1935 5.79
1936 5.79
1937 5.78
1938 5.77
1939 5.76
1940 5.76
1941 5.75
1942 5.74
1943 5.73
1944 5.73
1945 5.72
1946 5.71
1947 5.7
1948 5.7
1949 6.05
1950 6.93
1951 5.77
1952 5.96
1953 6.15
1954 6.31
1955 6.61
1956 6.67
1957 6.93
1958 6.82
1959 7.15
1960 7.25
1961 7.31
1962 7.09
1963 7.04
1964 7.27
1965 6.96
1966 7
1967 6.4
1968 5.85
1969 4.58
1970 3.9
1971 3.25
1972 2.77
1973 2.69
1974 2.3
1975 2.35
1976 2.26
1977 2.35
1978 2.2
1979 2.19
1980 2.44
1981 2.33
1982 2.24
1983 2.05
1984 2.11
1985 2.24
1986 2.04
1987 2.08
1988 2.32
1989 2.3
1990 2.44
1991 2.42
1992 2.61
1993 2.58
1994 2.53
1995 2.51
1996 2.49
1997 2.69
1998 2.46
1999 2.42
2000 2.33
2001 2.51
2002 2.57
2003 2.37
2004 2.42
2005 2.38
2006 2.26
2007 2.3
2008 2.25
2009 2.36
2010 2.2
2011 2.12
2012 2.02
2013 2.08