Year	Total
1800	7
1801	7
1802	7
1803	7
1804	7
1805	7
1806	7
1807	7
1808	7
1809	7
1810	7
1811	7
1812	7
1813	7
1814	7
1815	7
1816	7
1817	7
1818	7
1819	7
1820	7
1821	7
1822	7
1823	7
1824	7
1825	7
1826	7
1827	7
1828	7
1829	7
1830	7
1831	7
1832	7
1833	7
1834	7
1835	7
1836	7
1837	7
1838	7
1839	7
1840	7
1841	7
1842	7
1843	7
1844	7
1845	7
1846	7
1847	7
1848	7
1849	7
1850	7
1851	7
1852	7
1853	7
1854	7
1855	7
1856	7
1857	7
1858	7
1859	7
1860	7
1861	7
1862	7
1863	7
1864	7
1865	7
1866	7
1867	7
1868	7
1869	7
1870	7
1871	7
1872	7
1873	7
1874	7
1875	7
1876	7
1877	7
1878	7
1879	7
1880	7
1881	6.95
1882	6.89
1883	6.84
1884	6.78
1885	6.73
1886	6.68
1887	6.62
1888	6.57
1889	6.51
1890	6.46
1891	6.41
1892	6.35
1893	6.3
1894	6.24
1895	6.19
1896	6.14
1897	6.08
1898	6.05
1899	6.02
1900	5.99
1901	5.96
1902	5.92
1903	5.89
1904	5.86
1905	5.83
1906	5.8
1907	5.77
1908	5.73
1909	5.7
1910	5.67
1911	5.64
1912	5.61
1913	5.58
1914	5.54
1915	5.51
1916	5.48
1917	5.45
1918	5.42
1919	5.38
1920	5.35
1921	5.32
1922	5.29
1923	5.26
1924	5.23
1925	5.19
1926	5.16
1927	5.05
1928	4.94
1929	4.83
1930	4.71
1931	4.6
1932	4.49
1933	4.38
1934	4.26
1935	4.15
1936	4.04
1937	3.93
1938	3.81
1939	3.7
1940	3.59
1941	3.48
1942	3.37
1943	3.27
1944	3.16
1945	3.05
1946	2.95
1947	2.84
1948	2.73
1949	2.62
1950	2.52
1951	2.54
1952	2.59
1953	2.64
1954	2.68
1955	2.7
1956	2.73
1957	2.74
1958	2.73
1959	2.72
1960	2.69
1961	2.66
1962	2.61
1963	2.55
1964	2.49
1965	2.43
1966	2.37
1967	2.33
1968	2.29
1969	2.27
1970	2.25
1971	2.24
1972	2.23
1973	2.22
1974	2.19
1975	2.17
1976	2.14
1977	2.11
1978	2.1
1979	2.08
1980	2.08
1981	2.08
1982	2.09
1983	2.1
1984	2.11
1985	2.11
1986	2.1
1987	2.07
1988	2.03
1989	1.97
1990	1.9
1991	1.82
1992	1.73
1993	1.64
1994	1.55
1995	1.47
1996	1.4
1997	1.34
1998	1.29
1999	1.26
2000	1.24
2001	1.24
2002	1.24
2003	1.26
2004	1.29
2005	1.32
2006	1.36
2007	1.4
2008	1.45
2009	1.5
2010	1.54
2011	1.58
2012	1.62
2013	1.65
2014	1.67
2015	1.69
2016	1.7
2017	1.71
2018	1.72