Year	Total
1800	5.9
1801	5.9
1802	5.9
1803	5.9
1804	5.9
1805	5.9
1806	5.9
1807	5.9
1808	5.9
1809	5.9
1810	5.9
1811	5.9
1812	5.9
1813	5.9
1814	5.9
1815	5.9
1816	5.9
1817	5.9
1818	5.9
1819	5.9
1820	5.9
1821	5.9
1822	5.9
1823	5.9
1824	5.9
1825	5.9
1826	5.9
1827	5.9
1828	5.9
1829	5.9
1830	5.9
1831	5.9
1832	5.9
1833	5.9
1834	5.9
1835	5.9
1836	5.9
1837	5.9
1838	5.9
1839	5.9
1840	5.9
1841	5.9
1842	5.9
1843	5.9
1844	5.9
1845	5.9
1846	5.9
1847	5.9
1848	5.9
1849	5.9
1850	5.9
1851	5.9
1852	5.9
1853	5.9
1854	5.9
1855	5.9
1856	5.9
1857	5.9
1858	5.9
1859	5.9
1860	5.9
1861	5.9
1862	5.9
1863	5.9
1864	5.9
1865	5.9
1866	5.9
1867	5.9
1868	5.9
1869	5.9
1870	5.9
1871	5.9
1872	5.9
1873	5.9
1874	5.9
1875	5.9
1876	5.9
1877	5.9
1878	5.9
1879	5.9
1880	5.9
1881	5.9
1882	5.9
1883	5.9
1884	5.9
1885	5.9
1886	5.9
1887	5.9
1888	5.9
1889	5.9
1890	5.9
1891	5.9
1892	5.9
1893	5.9
1894	5.9
1895	5.9
1896	5.9
1897	5.9
1898	5.9
1899	5.9
1900	5.9
1901	5.88
1902	5.87
1903	5.86
1904	5.85
1905	5.85
1906	5.84
1907	5.83
1908	5.86
1909	5.89
1910	5.93
1911	5.96
1912	5.99
1913	5.94
1914	5.89
1915	5.85
1916	5.8
1917	5.75
1918	5.85
1919	5.95
1920	6.05
1921	6.15
1922	6.24
1923	6.26
1924	6.27
1925	6.28
1926	6.3
1927	6.31
1928	6.3
1929	6.28
1930	6.26
1931	6.25
1932	6.23
1933	6.2
1934	6.17
1935	6.14
1936	6.12
1937	6.09
1938	6.08
1939	6.08
1940	6.08
1941	6.07
1942	6.07
1943	6.06
1944	6.05
1945	6.04
1946	6.04
1947	6.03
1948	6.08
1949	6.14
1950	6.19
1951	6.23
1952	6.3
1953	6.37
1954	6.43
1955	6.49
1956	6.55
1957	6.59
1958	6.63
1959	6.66
1960	6.67
1961	6.68
1962	6.67
1963	6.65
1964	6.61
1965	6.55
1966	6.49
1967	6.42
1968	6.34
1969	6.26
1970	6.17
1971	6.09
1972	6
1973	5.91
1974	5.82
1975	5.72
1976	5.61
1977	5.49
1978	5.37
1979	5.24
1980	5.1
1981	4.96
1982	4.82
1983	4.68
1984	4.55
1985	4.43
1986	4.32
1987	4.22
1988	4.13
1989	4.04
1990	3.96
1991	3.89
1992	3.82
1993	3.74
1994	3.66
1995	3.58
1996	3.48
1997	3.38
1998	3.26
1999	3.14
2000	3.02
2001	2.9
2002	2.79
2003	2.69
2004	2.6
2005	2.53
2006	2.47
2007	2.41
2008	2.36
2009	2.31
2010	2.27
2011	2.22
2012	2.19
2013	2.16
2014	2.13
2015	2.1
2016	2.08
2017	2.06
2018	2.04