Year	Measure
1971	20.46255
1972	21.85682
1973	23.49427
1974	23.15027
1975	26.04135
1976	28.23055
1977	30.56737
1978	32.00278
1979	33.72796
1980	34.822
1981	31.19587
1982	32.99168
1983	33.39128
1984	36.00329
1985	42.85066
1986	42.83757
1987	43.05302
1988	38.1839
1989	40.93479
1990	44.87247
1991	41.56333
1992	44.95167
1993	51.48096
1994	54.83208
1995	58.05107
1996	58.50209
1997	65.42484
1998	65.81415
1999	69.06102
2000	76.27649
2001	69.25024
2002	73.90716
2003	80.81908
2004	81.33344
2005	75.57348
2006	89.1569
2007	90.27571
2008	95.00856
2009	100.25966
2010	125.40898
2011	155.71767
2012	157.31611
2013	186.82871
2014	216.77761