Year	Years
1800	35.7
1801	35.7
1802	35.7
1803	35.7
1804	35.7
1805	35.7
1806	35.7
1807	35.7
1808	35.7
1809	35.7
1810	35.7
1811	35.7
1812	35.7
1813	35.7
1814	35.7
1815	35.7
1816	35.7
1817	35.7
1818	35.7
1819	35.7
1820	35.7
1821	35.7
1822	35.7
1823	35.7
1824	35.7
1825	35.7
1826	35.7
1827	35.7
1828	35.7
1829	35.7
1830	35.7
1831	35.7
1832	35.7
1833	35.7
1834	35.7
1835	35.7
1836	35.7
1837	35.7
1838	35.7
1839	35.7
1840	35.7
1841	35.7
1842	35.7
1843	35.7
1844	35.7
1845	35.7
1846	35.7
1847	35.7
1848	35.7
1849	35.7
1850	35.7
1851	35.7
1852	35.7
1853	35.7
1854	35.7
1855	35.7
1856	35.7
1857	35.7
1858	35.7
1859	35.7
1860	35.7
1861	35.7
1862	35.7
1863	35.7
1864	35.7
1865	35.7
1866	35.7
1867	35.7
1868	35.7
1869	35.7
1870	35.7
1871	35.66
1872	35.62
1873	35.58
1874	35.54
1875	35.5
1876	35.47
1877	35.43
1878	35.39
1879	35.35
1880	35.31
1881	35.27
1882	35.23
1883	35.19
1884	35.15
1885	35.11
1886	35.07
1887	35.03
1888	35
1889	34.96
1890	34.92
1891	34.88
1892	34.84
1893	34.8
1894	34.76
1895	34.72
1896	34.68
1897	34.64
1898	34.6
1899	34.56
1900	34.53
1901	34.49
1902	34.45
1903	34.41
1904	34.37
1905	34.33
1906	34.29
1907	34.25
1908	34.21
1909	34.17
1910	34.13
1911	34.09
1912	34.06
1913	34.02
1914	33.98
1915	33.94
1916	33.9
1917	33.86
1918	29.9
1919	33.78
1920	33.74
1921	33.7
1922	33.66
1923	33.62
1924	33.59
1925	33.55
1926	33.51
1927	33.47
1928	33.43
1929	33.39
1930	33.35
1931	33.31
1932	33.27
1933	33.23
1934	33.19
1935	33.15
1936	33.12
1937	33.08
1938	33.04
1939	33
1940	32.96
1941	33.6
1942	34.24
1943	34.88
1944	35.53
1945	36.17
1946	36.8
1947	37.44
1948	38.07
1949	38.7
1950	39.33
1951	39.44
1952	39.74
1953	40.08
1954	40.43
1955	40.8
1956	41.21
1957	41.64
1958	42.08
1959	42.54
1960	42.98
1961	43.42
1962	43.83
1963	44.23
1964	44.6
1965	44.98
1966	45.4
1967	45.86
1968	46.38
1969	46.97
1970	47.6
1971	58.44
1972	59.5
1973	60.28
1974	61.21
1975	62.18
1976	62.91
1977	63.42
1978	63.71
1979	63.94
1980	64.08
1981	64.33
1982	64.72
1983	64.95
1984	65.26
1985	65.97
1986	66.72
1987	67.55
1988	68.33
1989	68.86
1990	69.43
1991	69.47
1992	69.98
1993	70.22
1994	70.68
1995	71.2
1996	71.88
1997	72.56
1998	73.29
1999	74.14
2000	74.83
2001	75.4
2002	75.9
2003	76.28
2004	76.68
2005	77.09
2006	77.49
2007	77.7
2008	77.91
2009	77.86
2010	77.92
2011	78.14
2012	78.47
2013	78.88
2014	79.34
2015	79.53
2016	79.7
2017	79.96
2018	80.21