Year	Percent
1970	97.00599
1971	97.40566
1972	97.79582
1973	98.05936
1974	98.42697
1975	98.78319
1976	99.12759
1977	99.46294
1978	99.78836
1979	100.10428
1980	100.4111
1981	100.70922
1982	100.999
1983	101.18227
1984	101.35922
1985	101.62835
1986	101.98675
1987	102.2409
1988	102.39631
1989	102.63876
1990	102.87511
1991	103.01686
1992	103.24277
1993	103.4662
1994	103.59589
1995	103.81033
1996	103.93305
1997	104.13907
1998	104.17349
1999	104.37247
2000	104.48718
2001	104.59952
2002	104.78807
2003	104.8174
2004	104.92308
2005	105.10671
2006	105.13208
2007	105.2356
2008	105.25926
2009	105.35977
2010	105.45852
2011	105.48341
2012	105.50787
2013	105.53191
2014	105.62984
2015	105.58269