Year	Measure
1820	515.3
1821	517.7
1822	520.1
1823	522.6
1824	525
1825	527.5
1826	530
1827	532.4
1828	534.9
1829	537.4
1830	540
1831	542.5
1832	545
1833	547.6
1834	550.2
1835	552.7
1836	555.3
1837	557.9
1838	560.6
1839	563.2
1840	565.8
1841	568.5
1842	571.1
1843	573.8
1844	576.5
1845	579.2
1846	581.9
1847	584.7
1848	587.4
1849	590.2
1850	592.9
1851	595.7
1852	598.5
1853	601.3
1854	604.1
1855	607
1856	609.8
1857	612.7
1858	615.5
1859	618.4
1860	621.3
1861	624.2
1862	627.2
1863	630.1
1864	633.1
1865	636
1866	639
1867	642
1868	645
1869	648
1870	651.1
1871	654.1
1872	657.2
1873	660.3
1874	663.4
1875	666.5
1876	669.6
1877	672.8
1878	675.9
1879	679.1
1880	682.3
1881	685.5
1882	688.7
1883	691.9
1884	695.2
1885	698.4
1886	701.7
1887	705
1888	708.3
1889	711.6
1890	714.9
1891	718.3
1892	721.7
1893	725
1894	728.4
1895	731.9
1896	735.3
1897	738.7
1898	742.2
1899	745.7
1900	749.2
1901	752.7
1902	756.2
1903	759.8
1904	763.3
1905	766.9
1906	770.5
1907	774.1
1908	777.8
1909	781.4
1910	785.1
1911	788.7
1912	792.4
1913	796.2
1914	808
1915	819.9
1916	832.1
1917	844.4
1918	856.9
1919	869.6
1920	882.5
1921	895.6
1922	908.8
1923	922.3
1924	936
1925	949.8
1926	963.9
1927	978.2
1928	992.7
1929	1007
1930	1022
1931	1037
1932	1053
1933	1068
1934	1084
1935	1100
1936	1117
1937	1133
1938	1150
1939	1167
1940	1184
1941	1202
1942	1220
1943	1238
1944	1256
1945	1275
1946	1294
1947	1313
1948	1332
1949	1352
1950	1372
1951	1418
1952	1429
1953	1450
1954	1497
1955	1508
1956	1529
1957	1549
1958	1554
1959	1603
1960	1778
1961	1956
1962	2310
1963	2382
1964	2663
1965	3000
1966	3048
1967	3252
1968	3022
1969	3068
1970	3873
1971	3833
1972	4188
1973	4295
1974	4649
1975	4684
1976	4703
1977	4706
1978	4685
1979	4607
1980	4561
1981	4721
1982	4848
1983	4707
1984	4637
1985	4751
1986	4745
1987	4959
1988	4621
1989	4714
1990	4633
1991	4538
1992	4422
1993	4432
1994	4556
1995	4694
1996	4755
1997	4825
1998	4879
1999	4965
2000	5005
2001	5036
2002	5138
2003	5236
2004	5334
2005	5456
2006	5551
2007	6252
2008	6373
2009	6378
2010	6426
2011	6367
2012	6409
2013	6509
2014	6564
2015	6622
2016	6679
2017	6729
2018	6781
2019	6832