Year	Percent
1970	92.83784
1971	93.35989
1972	93.86423
1973	94.10256
1974	94.58438
1975	95.04337
1976	95.3715
1977	95.80838
1978	96.11307
1979	96.52375
1980	96.92132
1981	97.3064
1982	97.67956
1983	98.04135
1984	98.49946
1985	98.83844
1986	99.16753
1987	99.4877
1988	99.79798
1989	100.1992
1990	100.49116
1991	100.87209
1992	101.24402
1993	101.51086
1994	101.86393
1995	102.20994
1996	102.45455
1997	102.78527
1998	103.01686
1999	103.24561
2000	103.55594
2001	103.77358
2002	104.07125
2003	104.19463
2004	104.39834
2005	104.5977
2006	104.71162
2007	104.98793
2008	105.09554
2009	105.20505
2010	105.30835
2011	105.41377
2012	105.59387
2013	105.61457
2014	105.71429
2015	105.7377