Year	Measure
1971	297.22581
1972	292.97667
1973	299.45978
1974	274.582
1975	285.39837
1976	250.62231
1977	254.80971
1978	255.80738
1979	258.87148
1980	264.68955
1981	261.9976
1982	265.23329
1983	267.46721
1984	264.42062
1985	261.53425
1986	267.82574
1987	277.09336
1988	273.54784
1989	261.60022
1990	261.92855
1991	259.91534
1992	265.72567
1993	282.63231
1994	277.61302
1995	291.03101
1996	302.62372
1997	321.55471
1998	338.31013
1999	344.04158
2000	357.923
2001	377.68757
2002	408.03811
2003	424.31074
2004	466.52469
2005	489.29319
2006	496.75521
2007	529.57398
2008	560.90769
2009	605.98395
2010	665.87834
2011	658.37097
2012	662.52902
2013	654.96287