Year	Measure
1800	639.8
1801	640.1
1802	640.3
1803	640.6
1804	640.8
1805	641.1
1806	641.3
1807	641.6
1808	641.8
1809	642.1
1810	642.3
1811	642.6
1812	642.8
1813	643.1
1814	643.3
1815	643.6
1816	643.8
1817	644.1
1818	644.3
1819	644.6
1820	644.8
1821	648.5
1822	652.2
1823	655.9
1824	659.6
1825	663.3
1826	667.1
1827	670.9
1828	674.7
1829	678.5
1830	682.4
1831	686.3
1832	690.2
1833	694.1
1834	698
1835	702
1836	706
1837	710
1838	714
1839	718.1
1840	722.1
1841	726.2
1842	730.4
1843	734.5
1844	738.7
1845	742.9
1846	747.1
1847	751.3
1848	755.6
1849	759.9
1850	764.2
1851	768.5
1852	772.9
1853	777.3
1854	781.7
1855	786.1
1856	790.6
1857	795.1
1858	799.6
1859	804.1
1860	808.7
1861	813.3
1862	817.9
1863	822.5
1864	827.2
1865	831.9
1866	836.6
1867	841.4
1868	846.2
1869	851
1870	855.8
1871	860.7
1872	865.5
1873	870.5
1874	875.4
1875	880.4
1876	885.4
1877	890.4
1878	895.4
1879	900.5
1880	905.6
1881	910.8
1882	915.9
1883	921.1
1884	926.4
1885	931.6
1886	895.1
1887	1046
1888	1005
1889	934.3
1890	929.9
1891	851.2
1892	931.2
1893	1055
1894	1198
1895	1108
1896	1220
1897	1199
1898	1230
1899	1304
1900	1275
1901	1306
1902	1418
1903	1320
1904	1458
1905	1290
1906	1232
1907	1183
1908	1291
1909	1340
1910	1429
1911	1319
1912	1424
1913	1495
1914	1427
1915	1468
1916	1304
1917	1144
1918	700
1919	603.1
1920	605.1
1921	553.5
1922	642.1
1923	739.1
1924	935.7
1925	1169
1926	1311
1927	1365
1928	1435
1929	1450
1930	1515
1931	1527
1932	1503
1933	1558
1934	1700
1935	1943
1936	2074
1937	2244
1938	2237
1939	2326
1940	2227
1941	2184
1942	2142
1943	2100
1944	2059
1945	2019
1946	1980
1947	2199
1948	2483
1949	2710
1950	2933
1951	2894
1952	3027
1953	3104
1954	3198
1955	3409
1956	3667
1957	3674
1958	3879
1959	3765
1960	4046
1961	4203
1962	4246
1963	4087
1964	4552
1965	4752
1966	4926
1967	5090
1968	5335
1969	5359
1970	5717
1971	5812
1972	5787
1973	6214
1974	6404
1975	6432
1976	6746
1977	6919
1978	7108
1979	7093
1980	7122
1981	7207
1982	7404
1983	7659
1984	7770
1985	7855
1986	8196
1987	8323
1988	8525
1989	8704
1990	8531
1991	8388
1992	7537
1993	6928
1994	6101
1995	5458
1996	5609
1997	6251
1998	6782
1999	7021
2000	7439
2001	7801
2002	8203
2003	8772
2004	9783
2005	10700
2006	11820
2007	12870
2008	14450
2009	14500
2010	15650
2011	16600
2012	16920
2013	17070
2014	17430
2015	17950
2016	18540
2017	19130
2018	19760
2019	20410