Year	Measure
1971	332.50933
1972	332.04083
1973	324.0001
1974	316.55437
1975	322.52413
1976	315.85645
1977	327.99895
1978	329.84096
1979	334.54238
1980	326.30633
1981	322.14098
1982	327.33358
1983	307.64302
1984	308.17515
1985	303.17886
1986	319.94191
1987	327.90926
1988	324.68073
1989	325.22211
1990	333.57803
1991	333.26679
1992	329.61093
1993	323.70675
1994	357.39984
1995	366.45934
1996	399.29058
1997	381.69931
1998	395.40391
1999	438.32713
2000	424.66401
2001	411.94087
2002	415.22853
2003	427.11737
2004	420.45095
2005	417.32239
2006	405.4264
2007	409.67822
2008	415.72636
2009	492.16457
2010	479.04998
2011	469.09039
2012	455.2819
2013	455.32808
2014	456.6742