Year Measure 1820 975.1 1821 985.6 1822 996.2 1823 1007 1824 1018 1825 1029 1826 1040 1827 1051 1828 1062 1829 1074 1830 1085 1831 1097 1832 1109 1833 1121 1834 1133 1835 1145 1836 1157 1837 1170 1838 1182 1839 1195 1840 1208 1841 1221 1842 1234 1843 1247 1844 1261 1845 1275 1846 1288 1847 1302 1848 1316 1849 1330 1850 1345 1851 1359 1852 1374 1853 1389 1854 1403 1855 1419 1856 1434 1857 1449 1858 1465 1859 1481 1860 1497 1861 1513 1862 1529 1863 1546 1864 1562 1865 1579 1866 1596 1867 1613 1868 1631 1869 1648 1870 1666 1871 1695 1872 1689 1873 1766 1874 1819 1875 1811 1876 1782 1877 1820 1878 1887 1879 1998 1880 2116 1881 2121 1882 1893 1883 1820 1884 1842 1885 1881 1886 1887 1887 1856 1888 1920 1889 2002 1890 2086 1891 2136 1892 2273 1893 2420 1894 2447 1895 2394 1896 2441 1897 2426 1898 2353 1899 2350 1900 2440 1901 2545 1902 2615 1903 2615 1904 2618 1905 2797 1906 2859 1907 2970 1908 2946 1909 2913 1910 3119 1911 3251 1912 3274 1913 3421 1914 3345 1915 3282 1916 2893 1917 2831 1918 2664 1919 3084 1920 2600 1921 2858 1922 3206 1923 3031 1924 3230 1925 3222 1926 3468 1927 3807 1928 3952 1929 4179 1930 4618 1931 4546 1932 4339 1933 4784 1934 4817 1935 4639 1936 4628 1937 4803 1938 4803 1939 5338 1940 5615 1941 6365 1942 7338 1943 7734 1944 8366 1945 8896 1946 9127 1947 9918 1948 9927 1949 9547 1950 9117 1951 8786 1952 8549 1953 9659 1954 10350 1955 11130 1956 11160 1957 10870 1958 11520 1959 11490 1960 11630 1961 11440 1962 12170 1963 13200 1964 14270 1965 15050 1966 16120 1967 15670 1968 14630 1969 14890 1970 15920 1971 17800 1972 18580 1973 19610 1974 20440 1975 20350 1976 21380 1977 23120 1978 24290 1979 25240 1980 26390 1981 27200 1982 27370 1983 26470 1984 27310 1985 28020 1986 29530 1987 31670 1988 31100 1989 30960 1990 31020 1991 30980 1992 29580 1993 29440 1994 30520 1995 30400 1996 31790 1997 33010 1998 34410 1999 35340 2000 36570 2001 37440 2002 36660 2003 37570 2004 40320 2005 41910 2006 42780 2007 44510 2008 44610 2009 41280 2010 39190 2011 39910 2012 40330 2013 41190 2014 42140 2015 43250 2016 44320 2017 45400 2018 46240 2019 47110