Year	Percent
1970	96.24277
1971	96.61972
1972	97.24518
1973	97.58065
1974	98.15789
1975	98.71465
1976	98.99749
1977	99.5098
1978	100
1979	100.46838
1980	100.91533
1981	101.56951
1982	101.97368
1983	102.35546
1984	102.93501
1985	103.49076
1986	103.81526
1987	104.3222
1988	104.61538
1989	105.08475
1990	105.53506
1991	106.14828
1992	106.56028
1993	106.94444
1994	107.31293
1995	107.84641
1996	108.01964
1997	108.34671
1998	108.83281
1999	109.13313
2000	109.42249
2001	109.85075
2002	110.1173
2003	110.35971
2004	110.6082
2005	110.98748
2006	111.20219
2007	111.4094
2008	111.75694
2009	111.94805
2010	112.13282
2011	112.43719
2012	112.60816
2013	112.77372
2014	112.91866
2015	113.0742