Year Total
1800 7.8
1801 7.8
1802 7.81
1803 7.81
1804 7.81
1805 7.82
1806 7.82
1807 7.82
1808 7.83
1809 7.83
1810 7.83
1811 7.83
1812 7.84
1813 7.84
1814 7.84
1815 7.85
1816 7.85
1817 7.85
1818 7.86
1819 7.86
1820 7.86
1821 7.87
1822 7.87
1823 7.87
1824 7.88
1825 7.88
1826 7.88
1827 7.89
1828 7.89
1829 7.89
1830 7.89
1831 7.9
1832 7.9
1833 7.9
1834 7.91
1835 7.91
1836 7.91
1837 7.92
1838 7.92
1839 7.92
1840 7.93
1841 7.93
1842 7.93
1843 7.94
1844 7.94
1845 7.94
1846 7.95
1847 7.95
1848 7.95
1849 7.95
1850 7.96
1851 7.96
1852 7.96
1853 7.97
1854 7.97
1855 7.97
1856 7.98
1857 7.98
1858 7.98
1859 7.99
1860 7.99
1861 7.99
1862 8
1863 8
1864 8
1865 8.01
1866 8.01
1867 8.01
1868 8.01
1869 8.02
1870 8.02
1871 8.02
1872 8.03
1873 8.03
1874 8.03
1875 8.04
1876 8.04
1877 8.04
1878 8.05
1879 8.05
1880 8.05
1881 8.06
1882 8.06
1883 8.06
1884 8.07
1885 8.07
1886 8.07
1887 8.07
1888 8.08
1889 8.08
1890 8.08
1891 8.09
1892 8.09
1893 8.09
1894 8.1
1895 8.1
1896 8.09
1897 8.08
1898 8.07
1899 8.06
1900 8.05
1901 8.04
1902 8.03
1903 8.02
1904 8.01
1905 8
1906 7.99
1907 7.98
1908 7.97
1909 7.96
1910 7.95
1911 7.94
1912 7.93
1913 7.92
1914 7.91
1915 7.9
1916 7.89
1917 7.88
1918 7.87
1919 7.86
1920 7.85
1921 7.84
1922 7.83
1923 7.82
1924 7.81
1925 7.8
1926 7.65
1927 7.5
1928 7.34
1929 7.19
1930 7.04
1931 6.89
1932 6.74
1933 6.58
1934 6.43
1935 6.28
1936 6.13
1937 5.98
1938 5.82
1939 5.67
1940 5.52
1941 4.56
1942 3.34
1943 1.82
1944 1.74
1945 2.39
1946 3.58
1947 4.1
1948 3.63
1949 4.05
1950 4.53
1951 4.51
1952 4.49
1953 4.48
1954 4.48
1955 4.49
1956 4.51
1957 4.53
1958 4.55
1959 4.56
1960 4.55
1961 4.51
1962 4.44
1963 4.32
1964 4.16
1965 3.98
1966 3.79
1967 3.61
1968 3.45
1969 3.31
1970 3.21
1971 3.12
1972 3.03
1973 2.94
1974 2.85
1975 2.75
1976 2.65
1977 2.56
1978 2.48
1979 2.42
1980 2.39
1981 2.37
1982 2.38
1983 2.41
1984 2.44
1985 2.48
1986 2.52
1987 2.55
1988 2.57
1989 2.57
1990 2.54
1991 2.48
1992 2.4
1993 2.3
1994 2.18
1995 1.8
1996 1.8
1997 1.7
1998 1.5
1999 1.4
2000 1.3
2001 1.2
2002 1.2
2003 1.4
2004 1.4
2005 1.4
2006 1.3
2007 1.4
2008 1.4
2009 1.6
2010 1.55
2011 1.5
2012 1.73
2013 1.71
2014 1.69
2015 1.66
2016 1.63
2017 1.6
2018 1.6