Year	Percent
1970	96.00912
1971	96.40853
1972	96.79204
1973	97.16776
1974	97.52954
1975	97.77778
1976	98.12109
1977	98.4552
1978	98.78049
1979	99.19679
1980	99.40535
1981	99.70617
1982	100
1983	100.28681
1984	100.47259
1985	100.84191
1986	101.11008
1987	101.28088
1988	101.53986
1989	101.79372
1990	102.04263
1991	102.19877
1992	102.44115
1993	102.59067
1994	102.82534
1995	103.05603
1996	103.19596
1997	103.41667
1998	103.55078
1999	103.76432
2000	103.80875
2001	104.01606
2002	104.14013
2003	104.17981
2004	104.37842
2005	104.41518
2006	104.60829
2007	104.64231
2008	104.75472
2009	104.78684
2010	104.97033
2011	105.00368
2012	105.03282
2013	105.13748
2014	105.24049
2015	105.19573