Year	Measure
1971	3629.59456
1972	3158.75706
1973	3285.54739
1974	2845.35518
1975	3495.05163
1976	3803.82352
1977	5490.27224
1978	5597.22362
1979	5849.81198
1980	6938.02092
1981	7914.20198
1982	8126.51308
1983	7433.21788
1984	9160.15057
1985	9861.16982
1986	10585.56749
1987	11084.6354
1988	10716.4059
1989	11666.45805
1990	10979.65405
1991	11922.62539
1992	10714.332
1993	10652.13135
1994	11188.16191
1995	11305.33114
1996	11368.97652
1997	11435.91135
1998	11125.36569
1999	10789.94914
2000	9991.42357
2001	12087.10439
2002	11369.47798
2003	10484.09458
2004	10238.10089
2005	9716.63382
2006	8812.96642
2007	8295.73464
2008	8604.06441
2009	7820.25484
2010	7458.87946
2011	7418.41377
2012	7683.8844
2013	7766.66537
2014	7769.23474