Year	Percent
1970	95.96929
1971	96.42857
1972	96.86924
1973	97.29242
1974	97.69912
1975	98.09359
1976	98.63946
1977	99
1978	99.509
1979	99.83949
1980	100.15748
1981	100.61824
1982	101.06222
1983	101.49031
1984	101.75439
1985	102.15517
1986	102.54237
1987	102.77393
1988	103.27422
1989	103.48525
1990	103.82082
1991	104.28016
1992	104.46429
1993	104.76788
1994	105.06173
1995	105.34629
1996	105.7485
1997	106.01415
1998	106.14849
1999	106.51429
2000	106.75676
2001	106.99223
2002	107.21311
2003	107.43534
2004	107.64331
2005	107.74059
2006	108.04954
2007	108.13835
2008	108.32497
2009	108.51485
2010	108.69141
2011	108.76686
2012	108.93536
2013	109.00563
2014	109.17516
2015	109.24062