Year	Years
1800	38.5
1801	38.5
1802	38.5
1803	38.5
1804	38.5
1805	38.5
1806	38.5
1807	38.5
1808	38.5
1809	38.5
1810	38.5
1811	38.5
1812	38.5
1813	38.5
1814	38.5
1815	38.5
1816	38.5
1817	38.5
1818	38.5
1819	38.5
1820	38.5
1821	38.5
1822	38.5
1823	38.5
1824	38.5
1825	38.5
1826	38.5
1827	38.5
1828	38.5
1829	38.5
1830	38.5
1831	38.5
1832	38.5
1833	38.5
1834	38.5
1835	38.5
1836	38.5
1837	38.5
1838	38.5
1839	38.5
1840	38.51
1841	38.51
1842	38.51
1843	38.51
1844	38.51
1845	38.51
1846	38.51
1847	38.51
1848	38.51
1849	38.51
1850	38.51
1851	38.51
1852	38.51
1853	38.51
1854	38.51
1855	38.51
1856	38.51
1857	38.51
1858	38.51
1859	38.51
1860	38.51
1861	38.51
1862	38.51
1863	38.51
1864	38.51
1865	38.51
1866	38.51
1867	38.51
1868	38.51
1869	38.51
1870	38.51
1871	38.5
1872	38.49
1873	38.47
1874	38.46
1875	38.45
1876	38.44
1877	38.43
1878	38.41
1879	38.4
1880	38.39
1881	38.38
1882	38.37
1883	38.35
1884	38.34
1885	38.33
1886	38.32
1887	38.31
1888	38.29
1889	38.28
1890	38.27
1891	38.26
1892	38.25
1893	38.23
1894	38.22
1895	38.21
1896	38.84
1897	39.47
1898	40.11
1899	40.74
1900	41.37
1901	41.99
1902	42.62
1903	43.25
1904	43.88
1905	44.51
1906	44.74
1907	44.96
1908	45.2
1909	45.43
1910	45.65
1911	45.88
1912	46.11
1913	46.34
1914	46.57
1915	46.79
1916	46.88
1917	46.96
1918	25.77
1919	47.13
1920	47.21
1921	47.29
1922	47.38
1923	47.46
1924	47.54
1925	47.63
1926	47.61
1927	47.6
1928	47.58
1929	47.57
1930	47.55
1931	47.54
1932	47.52
1933	47.51
1934	47.49
1935	47.48
1936	47.46
1937	47.45
1938	48.25
1939	49.05
1940	49.85
1941	50.65
1942	51.45
1943	52.24
1944	53.95
1945	55.66
1946	57.37
1947	59.07
1948	60.78
1949	62.49
1950	64.19
1951	64.4
1952	64.82
1953	65.22
1954	65.61
1955	65.99
1956	66.35
1957	66.7
1958	67.02
1959	67.35
1960	67.66
1961	67.96
1962	68.25
1963	68.54
1964	68.82
1965	69.09
1966	69.35
1967	69.6
1968	69.84
1969	70.08
1970	70.31
1971	70.56
1972	70.73
1973	70.91
1974	51.44
1975	71.15
1976	71.26
1977	72.17
1978	72.59
1979	73.01
1980	72.84
1981	73.32
1982	73.45
1983	73.84
1984	73.88
1985	74.04
1986	74.37
1987	74.14
1988	74.4
1989	74.6
1990	74.93
1991	74.97
1992	75.26
1993	75.5
1994	75.43
1995	75.72
1996	76.12
1997	76.24
1998	76.39
1999	76.63
2000	76.83
2001	77.27
2002	77.47
2003	77.74
2004	77.92
2005	78.04
2006	78.66
2007	78.95
2008	79.25
2009	79.56
2010	79.88
2011	80.22
2012	80.58
2013	80.64
2014	80.5
2015	80.47
2016	80.47
2017	80.63
2018	80.79