Year	Measure
1971	298.74186
1972	300.6923
1973	303.39342
1974	302.97957
1975	302.07866
1976	300.88921
1977	301.79474
1978	301.67983
1979	304.81954
1980	306.11335
1981	304.30566
1982	305.52706
1983	308.30903
1984	308.87455
1985	304.68598
1986	307.96913
1987	306.91083
1988	307.19113
1989	304.12549
1990	308.76541
1991	310.55642
1992	309.6166
1993	309.23113
1994	311.82304
1995	313.68394
1996	313.79122
1997	316.8993
1998	318.49579
1999	329.53703
2000	341.50817
2001	346.60452
2002	344.67667
2003	348.96832
2004	348.97864
2005	356.14344
2006	351.99558
2007	355.06791
2008	363.86649
2009	370.91518
2010	377.84673
2011	386.73821
2012	365.36229
2013	401.3714
2014	412.72448