Year Total
1800 4.5
1801 4.5
1802 4.5
1803 4.5
1804 4.5
1805 4.5
1806 4.5
1807 4.5
1808 4.5
1809 4.5
1810 4.5
1811 4.5
1812 4.5
1813 4.5
1814 4.5
1815 4.5
1816 4.5
1817 4.5
1818 4.5
1819 4.5
1820 4.5
1821 4.5
1822 4.5
1823 4.5
1824 4.5
1825 4.5
1826 4.5
1827 4.5
1828 4.5
1829 4.5
1830 4.5
1831 4.5
1832 4.5
1833 4.5
1834 4.5
1835 4.5
1836 4.5
1837 4.5
1838 4.5
1839 4.5
1840 4.5
1841 4.5
1842 4.5
1843 4.5
1844 4.5
1845 4.5
1846 4.5
1847 4.5
1848 4.5
1849 4.5
1850 4.5
1851 4.47
1852 4.44
1853 4.41
1854 4.38
1855 4.35
1856 4.33
1857 4.3
1858 4.27
1859 4.24
1860 4.21
1861 4.18
1862 4.15
1863 4.12
1864 4.09
1865 4.1
1866 4.11
1867 4.12
1868 4.14
1869 4.15
1870 4.16
1871 4.17
1872 4.18
1873 4.19
1874 4.2
1875 4.21
1876 4.22
1877 4.23
1878 4.24
1879 4.23
1880 4.22
1881 4.21
1882 4.19
1883 4.18
1884 4.17
1885 4.16
1886 4.15
1887 4.38
1888 4.3
1889 4.38
1890 4.24
1891 4.16
1892 4.06
1893 4.15
1894 3.86
1895 3.9
1896 3.9
1897 3.95
1898 3.93
1899 3.89
1900 3.97
1901 4.07
1902 4.16
1903 4.29
1904 4.11
1905 4.13
1906 4.17
1907 3.99
1908 3.94
1909 3.89
1910 4.12
1911 5.02
1912 4.54
1913 4.23
1914 4.1
1915 4.24
1916 4.17
1917 4.08
1918 3.86
1919 3.59
1920 4.37
1921 4.21
1922 4.3
1923 4.32
1924 4.26
1925 4.24
1926 4.36
1927 4.03
1928 4.15
1929 3.89
1930 3.86
1931 3.86
1932 3.89
1933 3.88
1934 3.74
1935 3.59
1936 3.45
1937 3.39
1938 3.34
1939 3.28
1940 3.22
1941 3.12
1942 3.14
1943 3.27
1944 3.28
1945 3.39
1946 3.29
1947 3.14
1948 3.42
1949 3.23
1950 3.1
1951 3.1
1952 3.1
1953 3.1
1954 3.1
1955 3.1
1956 3.11
1957 3.12
1958 3.13
1959 3.15
1960 3.16
1961 3.18
1962 3.19
1963 3.19
1964 3.19
1965 3.18
1966 3.16
1967 3.13
1968 3.09
1969 3.05
1970 2.99
1971 2.94
1972 2.88
1973 2.83
1974 2.77
1975 2.71
1976 2.65
1977 2.57
1978 2.49
1979 2.39
1980 2.29
1981 2.18
1982 2.07
1983 1.97
1984 1.87
1985 1.78
1986 1.71
1987 1.65
1988 1.6
1989 1.56
1990 1.52
1991 1.5
1992 1.48
1993 1.47
1994 1.46
1995 1.46
1996 1.45
1997 1.45
1998 1.46
1999 1.46
2000 1.46
2001 1.46
2002 1.45
2003 1.44
2004 1.43
2005 1.42
2006 1.4
2007 1.38
2008 1.36
2009 1.34
2010 1.33
2011 1.31
2012 1.29
2013 1.28
2014 1.26
2015 1.25
2016 1.25
2017 1.24
2018 1.24