Year	Total
1800	6.28
1801	6.26
1802	6.25
1803	6.23
1804	6.22
1805	6.2
1806	6.19
1807	6.17
1808	6.16
1809	6.14
1810	6.12
1811	6.11
1812	6.09
1813	6.08
1814	6.06
1815	6.05
1816	6.03
1817	6.03
1818	6.16
1819	6.3
1820	6.03
1821	6.3
1822	6.03
1823	5.76
1824	5.49
1825	6.83
1826	6.16
1827	6.3
1828	6.22
1829	6.14
1830	6.06
1831	5.98
1832	5.9
1833	6.43
1834	6.83
1835	5.9
1836	6.3
1837	6.57
1838	6.03
1839	6.43
1840	6.57
1841	6.16
1842	6.43
1843	6.3
1844	6.03
1845	5.36
1846	5.49
1847	5.09
1848	4.82
1849	5.49
1850	5.63
1851	5.63
1852	5.49
1853	5.63
1854	5.36
1855	4.82
1856	5.36
1857	5.76
1858	6.3
1859	6.57
1860	6.57
1861	6.43
1862	6.97
1863	6.57
1864	6.2
1865	5.83
1866	5.46
1867	5.09
1868	5.63
1869	5.63
1870	6.16
1871	5.76
1872	5.49
1873	5.76
1874	5.76
1875	5.49
1876	5.49
1877	5.23
1878	5.23
1879	5.36
1880	5.23
1881	5.09
1882	5.23
1883	5.23
1884	5.09
1885	5.36
1886	5.36
1887	5.36
1888	5.49
1889	5.76
1890	5.63
1891	5.63
1892	5.36
1893	5.63
1894	5.9
1895	5.9
1896	5.76
1897	5.63
1898	5.49
1899	5.49
1900	5.49
1901	5.36
1902	5.36
1903	5.09
1904	5.09
1905	4.96
1906	5.09
1907	5.09
1908	4.96
1909	4.96
1910	4.82
1911	4.69
1912	4.56
1913	4.69
1914	4.82
1915	3.89
1916	3.62
1917	3.22
1918	3.22
1919	4.42
1920	4.69
1921	4.4
1922	4.73
1923	4.82
1924	4.69
1925	4.74
1926	4.44
1927	4.23
1928	4.29
1929	4.26
1930	4.33
1931	4.05
1932	3.87
1933	3.55
1934	3.56
1935	3.49
1936	3.51
1937	3.33
1938	3.25
1939	3.22
1940	3.19
1941	3.16
1942	3.14
1943	3.11
1944	3.08
1945	3.05
1946	3.02
1947	3.47
1948	3.87
1949	3.88
1950	3.6
1951	3.62
1952	3.64
1953	3.65
1954	3.64
1955	3.6
1956	3.55
1957	3.47
1958	3.37
1959	3.25
1960	3.11
1961	2.96
1962	2.82
1963	2.69
1964	2.57
1965	2.48
1966	2.41
1967	2.35
1968	2.31
1969	2.28
1970	2.25
1971	2.24
1972	2.23
1973	2.22
1974	2.22
1975	2.22
1976	2.22
1977	2.23
1978	2.25
1979	2.27
1980	2.28
1981	2.3
1982	2.3
1983	2.3
1984	2.28
1985	2.26
1986	2.23
1987	2.2
1988	2.16
1989	2.12
1990	2.08
1991	2.03
1992	1.97
1993	1.9
1994	1.82
1995	1.73
1996	1.65
1997	1.56
1998	1.48
1999	1.41
2000	1.35
2001	1.31
2002	1.28
2003	1.28
2004	1.28
2005	1.3
2006	1.32
2007	1.34
2008	1.36
2009	1.37
2010	1.37
2011	1.36
2012	1.34
2013	1.33
2014	1.32
2015	1.31
2016	1.3
2017	1.29
2018	1.29