Year	Percent
1970	93.92625
1971	94.26752
1972	94.80249
1973	95.12195
1974	95.61753
1975	96.10136
1976	96.37405
1977	97.00375
1978	97.43119
1979	97.66607
1980	98.23944
1981	98.61831
1982	98.98477
1983	99.33665
1984	99.8374
1985	100.15949
1986	100.62598
1987	101.07527
1988	101.35542
1989	101.77515
1990	102.03193
1991	102.56776
1992	102.80112
1993	103.16369
1994	103.51351
1995	103.85126
1996	104.17755
1997	104.35897
1998	104.79193
1999	105.08685
2000	105.36585
2001	105.64226
2002	105.90319
2003	106.03949
2004	106.28571
2005	106.64414
2006	106.87361
2007	107.09607
2008	107.31183
2009	107.41525
2010	107.62004
2011	107.81893
2012	108.01217
2013	108.2
2014	108.28402
2015	108.46304