Year	Measure
1971	225.66827
1972	244.72757
1973	222.47533
1974	262.18284
1975	270.6717
1976	305.80881
1977	336.94195
1978	325.59932
1979	250.20943
1980	259.6995
1981	267.75011
1982	277.10466
1983	293.37242
1984	295.91742
1985	288.48039
1986	283.65118
1987	297.45479
1988	293.31321
1989	323.28344
1990	308.35564
1991	301.40665
1992	304.29825
1993	293.90636
1994	281.14959
1995	293.56745
1996	313.77778
1997	352.85712
1998	344.37963
1999	331.53792
2000	347.73641
2001	346.61569
2002	355.58673
2003	370.93014
2004	396.63235
2005	416.96658
2006	429.70813
2007	464.13452
2008	477.96892
2009	484.06614
2010	514.14124
2011	537.03455
2012	579.53674
2013	598.07456
2014	580.47917