Year	Percent
1970	90.9292
1971	91.37931
1972	92.01681
1973	92.43354
1974	93.02789
1975	93.59223
1976	93.95085
1977	94.47514
1978	95.1526
1979	95.62937
1980	96.08844
1981	96.52318
1982	97.09677
1983	97.48823
1984	98.01527
1985	98.36553
1986	98.84393
1987	99.29775
1988	99.72678
1989	100.1328
1990	100.51613
1991	100.87719
1992	101.21655
1993	101.53483
1994	101.83276
1995	102.22222
1996	102.38612
1997	102.75716
1998	103.01142
1999	103.25534
2000	103.49301
2001	103.72184
2002	103.84615
2003	104.06427
2004	104.27907
2005	104.39158
2006	104.59459
2007	104.70693
2008	104.8119
2009	104.91803
2010	105.11073
2011	105.21008
2012	105.3112
2013	105.32787
2014	105.51053
2015	105.52442