Year	Measure
1820	1138
1821	1143
1822	1149
1823	1154
1824	1160
1825	1165
1826	1171
1827	1177
1828	1182
1829	1188
1830	1194
1831	1199
1832	1205
1833	1211
1834	1217
1835	1223
1836	1228
1837	1234
1838	1240
1839	1246
1840	1252
1841	1258
1842	1264
1843	1270
1844	1276
1845	1282
1846	1289
1847	1295
1848	1301
1849	1307
1850	1313
1851	1320
1852	1326
1853	1332
1854	1339
1855	1345
1856	1352
1857	1358
1858	1365
1859	1371
1860	1378
1861	1384
1862	1391
1863	1398
1864	1404
1865	1411
1866	1418
1867	1425
1868	1431
1869	1438
1870	1445
1871	1467
1872	1489
1873	1511
1874	1534
1875	1557
1876	1580
1877	1604
1878	1628
1879	1652
1880	1677
1881	1702
1882	1728
1883	1753
1884	1780
1885	1806
1886	1833
1887	1861
1888	1889
1889	1917
1890	1946
1891	1961
1892	1977
1893	1992
1894	2008
1895	2024
1896	2039
1897	2055
1898	2072
1899	2088
1900	2104
1901	2141
1902	2179
1903	2217
1904	2256
1905	2296
1906	2336
1907	2377
1908	2419
1909	2462
1910	2505
1911	2549
1912	2594
1913	2639
1914	2517
1915	2400
1916	2288
1917	2182
1918	2080
1919	1984
1920	1892
1921	1804
1922	1720
1923	1640
1924	1564
1925	1587
1926	2012
1927	2159
1928	2098
1929	2031
1930	2210
1931	2501
1932	2485
1933	2494
1934	2252
1935	2126
1936	2569
1937	2695
1938	2744
1939	2757
1940	2664
1941	2696
1942	2546
1943	2604
1944	2387
1945	1846
1946	2012
1947	2193
1948	2391
1949	2606
1950	2841
1951	3422
1952	3258
1953	3588
1954	3484
1955	3695
1956	3661
1957	4010
1958	4315
1959	4617
1960	5010
1961	5286
1962	5670
1963	5881
1964	6293
1965	6624
1966	7098
1967	7433
1968	7516
1969	7821
1970	8213
1971	8434
1972	8793
1973	9092
1974	9315
1975	10030
1976	10290
1977	10140
1978	10360
1979	10750
1980	10400
1981	10640
1982	10960
1983	10730
1984	11060
1985	10710
1986	10980
1987	10980
1988	10900
1989	10700
1990	9630
1991	8943
1992	8400
1993	8486
1994	8730
1995	9090
1996	8331
1997	7957
1998	8373
1999	8651
2000	9205
2001	9682
2002	10260
2003	10800
2004	11620
2005	12460
2006	13340
2007	14280
2008	15230
2009	14480
2010	14650
2011	15280
2012	15460
2013	15690
2014	16020
2015	16500
2016	17090
2017	17690
2018	18310
2019	18950