Year	Total
1800	8.1
1801	8.1
1802	8.1
1803	8.1
1804	8.1
1805	8.1
1806	8.1
1807	8.1
1808	8.1
1809	8.1
1810	8.1
1811	8.1
1812	8.1
1813	8.1
1814	8.1
1815	8.1
1816	8.1
1817	8.1
1818	8.1
1819	8.1
1820	8.1
1821	8.1
1822	8.1
1823	8.1
1824	8.1
1825	8.1
1826	8.1
1827	8.1
1828	8.1
1829	8.1
1830	8.1
1831	8.1
1832	8.1
1833	8.1
1834	8.1
1835	8.1
1836	8.1
1837	8.1
1838	8.1
1839	8.1
1840	8.1
1841	8.1
1842	8.1
1843	8.1
1844	8.1
1845	8.1
1846	8.1
1847	8.1
1848	8.1
1849	8.1
1850	8.1
1851	8.1
1852	8.1
1853	8.1
1854	8.1
1855	8.1
1856	8.1
1857	8.1
1858	8.1
1859	8.1
1860	8.1
1861	8.1
1862	8.1
1863	8.1
1864	8.1
1865	8.1
1866	8.1
1867	8.1
1868	8.1
1869	8.1
1870	8.1
1871	8.1
1872	8.1
1873	8.1
1874	8.1
1875	8.1
1876	8.1
1877	8.1
1878	8.1
1879	8.1
1880	8.1
1881	8.1
1882	8.1
1883	8.1
1884	8.1
1885	8.1
1886	8.1
1887	8.1
1888	8.1
1889	8.1
1890	8.1
1891	8.1
1892	8.1
1893	8.1
1894	8.1
1895	8.1
1896	8.07
1897	8.04
1898	8.01
1899	7.98
1900	7.95
1901	7.92
1902	7.89
1903	7.86
1904	7.83
1905	7.8
1906	7.77
1907	7.74
1908	7.71
1909	7.68
1910	7.65
1911	7.62
1912	7.59
1913	7.56
1914	7.53
1915	7.5
1916	7.47
1917	7.44
1918	7.41
1919	7.38
1920	7.35
1921	7.32
1922	7.29
1923	7.26
1924	7.23
1925	7.2
1926	7.14
1927	7.08
1928	7.01
1929	6.95
1930	6.89
1931	6.82
1932	6.75
1933	6.68
1934	6.6
1935	6.52
1936	6.44
1937	6.36
1938	6.28
1939	6.19
1940	6.11
1941	6.02
1942	5.93
1943	5.84
1944	5.75
1945	5.66
1946	5.58
1947	5.5
1948	5.42
1949	5.34
1950	5.26
1951	5.25
1952	5.25
1953	5.28
1954	5.32
1955	5.39
1956	5.48
1957	5.58
1958	5.68
1959	5.79
1960	5.88
1961	5.94
1962	5.96
1963	5.95
1964	5.89
1965	5.79
1966	5.66
1967	5.51
1968	5.35
1969	5.19
1970	5.02
1971	4.85
1972	4.68
1973	4.51
1974	4.34
1975	4.18
1976	4.02
1977	3.87
1978	3.73
1979	3.61
1980	3.5
1981	3.41
1982	3.34
1983	3.29
1984	3.26
1985	3.24
1986	3.22
1987	3.2
1988	3.18
1989	3.14
1990	3.09
1991	3.02
1992	2.93
1993	2.82
1994	2.71
1995	2.58
1996	2.45
1997	2.33
1998	2.21
1999	2.11
2000	2.03
2001	1.96
2002	1.91
2003	1.87
2004	1.84
2005	1.82
2006	1.82
2007	1.84
2008	1.87
2009	1.91
2010	1.96
2011	2.01
2012	2.05
2013	2.08
2014	2.09
2015	2.09
2016	2.08
2017	2.06
2018	2.04