Year	Percent
1970	96.30119
1971	96.62776
1972	96.94268
1973	97.24656
1974	97.53998
1975	97.94438
1976	98.21641
1977	98.59649
1978	98.73563
1979	99.09502
1980	99.33259
1981	99.67141
1982	99.89224
1983	100.21231
1984	100.41797
1985	100.5144
1986	100.81136
1987	100.999
1988	101.1811
1989	101.45631
1990	101.62679
1991	101.79245
1992	102.04842
1993	102.11203
1994	102.26449
1995	102.50447
1996	102.55732
1997	102.698
1998	102.92096
1999	103.05344
2000	103.18258
2001	103.30852
2002	103.34967
2003	103.47054
2004	103.58852
2005	103.6249
2006	103.74123
2007	103.85208
2008	103.96341
2009	103.99698
2010	104.10448
2011	104.13589
2012	104.16667
2013	104.27227
2014	104.30416
2015	104.40654