Year	Measure
1800	809.2
1820	809.2
1950	352
1951	355.2
1952	368.5
1953	363.3
1954	395.8
1955	378.2
1956	417.5
1957	434
1958	444
1959	474.6
1960	489.7
1961	472.2
1962	496.9
1963	519.8
1964	492.2
1965	502
1966	511.1
1967	523.4
1968	533.2
1969	527.5
1970	472.6
1971	449.5
1972	421.6
1973	567.9
1974	480.7
1975	423.4
1976	470.2
1977	525
1978	593.5
1979	608.2
1980	606.6
1981	597.4
1982	624.5
1983	648.6
1984	677.9
1985	706.9
1986	724.2
1987	683.9
1988	675.4
1989	666.8
1990	642.9
1991	666.8
1992	682.3
1993	677.3
1994	680.6
1995	708.2
1996	730.4
1997	734.3
1998	729.5
1999	793.3
2000	833.4
2001	865
2002	896.2
2003	926.1
2004	1305
2005	1453
2006	1571
2007	1712
2008	1797
2009	1769
2010	1858
2011	1970
2012	2077
2013	2193
2014	2329
2015	2476
2016	2633
2017	2802
2018	2983