Year	Measure
1971	361.51319
1972	363.13096
1973	355.97946
1974	352.01434
1975	347.81788
1976	369.87108
1977	341.76389
1978	344.86628
1979	334.74025
1980	336.8456
1981	337.20541
1982	347.198
1983	377.69471
1984	355.07792
1985	359.30528
1986	343.79944
1987	339.92057
1988	321.92816
1989	325.26164
1990	322.59901
1991	327.79615
1992	315.11524
1993	308.5225
1994	258.85171
1995	287.43755
1996	263.33885
1997	244.91421
1998	238.21394
1999	227.93546
2000	220.06574
2001	239.98569
2002	235.25614
2003	270.07477
2004	278.60075
2005	292.28375
2006	369.18955
2007	316.86822
2008	327.60133
2009	361.91378
2010	382.26381
2011	494.76547
2012	552.27941
2013	552.48703
2014	539.53162