Year	Measure
1800	376
1820	376
1913	448.4
1950	481
1951	502.3
1952	510.2
1953	521
1954	543.6
1955	553.3
1956	565.4
1957	576.3
1958	583.8
1959	606.9
1960	621.4
1961	650.6
1962	686.4
1963	637.6
1964	666.6
1965	699.1
1966	700.5
1967	708.8
1968	716.3
1969	723.1
1970	733.7
1971	741.5
1972	741.7
1973	758.7
1974	795.6
1975	812.1
1976	873.5
1977	874.7
1978	879.3
1979	862.6
1980	873.7
1981	860.2
1982	857.3
1983	848.7
1984	833.2
1985	807.7
1986	801.2
1987	805.6
1988	831.9
1989	843.6
1990	834.5
1991	797.5
1992	794.3
1993	809.6
1994	815.2
1995	825.5
1996	838.4
1997	869.4
1998	897.2
1999	909.9
2000	906.6
2001	934.8
2002	945.6
2003	934.4
2004	937.5
2005	946
2006	949.9
2007	946.2
2008	970.9
2009	944.6
2010	939.4
2011	952.3
2012	965.7
2013	984.7
2014	1011
2015	1039
2016	1073
2017	1245
2018	1435