Year Measure 1800 1337 1801 1338 1802 1339 1803 1341 1804 1342 1805 1344 1806 1345 1807 1346 1808 1348 1809 1349 1810 1351 1811 1352 1812 1353 1813 1355 1814 1356 1815 1358 1816 1359 1817 1361 1818 1362 1819 1363 1820 1365 1821 1373 1822 1382 1823 1391 1824 1400 1825 1409 1826 1417 1827 1426 1828 1435 1829 1445 1830 1454 1831 1463 1832 1472 1833 1482 1834 1491 1835 1500 1836 1510 1837 1519 1838 1529 1839 1539 1840 1548 1841 1558 1842 1568 1843 1578 1844 1588 1845 1598 1846 1608 1847 1618 1848 1629 1849 1639 1850 1649 1851 1660 1852 1670 1853 1681 1854 1692 1855 1702 1856 1713 1857 1724 1858 1735 1859 1746 1860 1757 1861 1768 1862 1779 1863 1790 1864 1802 1865 1813 1866 1825 1867 1836 1868 1848 1869 1860 1870 1871 1871 1883 1872 1895 1873 1907 1874 1919 1875 1931 1876 1944 1877 1956 1878 1968 1879 1981 1880 1993 1881 2006 1882 2019 1883 2031 1884 2044 1885 2057 1886 1978 1887 2313 1888 2225 1889 2068 1890 2060 1891 1887 1892 2066 1893 2341 1894 2662 1895 2463 1896 2713 1897 2667 1898 2738 1899 2906 1900 2843 1901 2914 1902 3167 1903 2948 1904 3260 1905 2886 1906 2758 1907 2650 1908 2894 1909 3005 1910 3206 1911 2962 1912 3201 1913 3362 1914 3211 1915 3304 1916 2938 1917 2580 1918 2064 1919 1899 1920 2468 1921 2838 1922 3264 1923 3493 1924 3552 1925 3718 1926 3820 1927 4084 1928 4324 1929 4339 1930 4257 1931 4121 1932 4072 1933 4315 1934 4773 1935 4939 1936 5236 1937 5496 1938 5733 1939 5442 1940 5143 1941 5047 1942 4952 1943 4859 1944 4768 1945 4678 1946 4591 1947 5101 1948 5763 1949 6294 1950 6818 1951 6732 1952 7046 1953 7228 1954 7453 1955 7948 1956 8557 1957 8579 1958 9062 1959 8803 1960 9466 1961 9832 1962 9934 1963 9562 1964 10650 1965 11120 1966 11530 1967 11910 1968 12480 1969 12540 1970 13380 1971 13600 1972 13540 1973 14540 1974 14820 1975 14720 1976 15270 1977 15500 1978 15750 1979 15540 1980 15440 1981 15450 1982 15710 1983 16070 1984 16130 1985 16130 1986 16650 1987 16720 1988 16940 1989 17110 1990 16590 1991 15610 1992 12290 1993 10330 1994 9344 1995 9846 1996 10320 1997 11060 1998 11880 1999 11680 2000 12150 2001 12960 2002 13890 2003 15290 2004 16460 2005 17770 2006 19270 2007 21280 2008 22010 2009 18850 2010 19440 2011 22320 2012 23450 2013 24340 2014 25270 2015 26280 2016 27360 2017 28500 2018 29720 2019 31000