Year	Percent
1971	94.5074
1973	97.26486
1974	98.06
1975	98.91757
1976	98.72069
1977	101.94334
1978	101.84066
1979	101.08667
1980	98.6627
1981	99.51717
1982	100.36554
1984	99.78212
1985	99.51261
1986	98.1311
1987	97.3943
1988	96.08188
1989	95.02004
1990	94.79883
1991	99.8322
1992	101.28681
1993	100.46254
1998	97.65119
1999	98.17912
2000	97.1619
2001	101.27548
2002	102.85865
2003	103.23584
2004	102.55807
2005	100.57807
2006	96.65455
2007	97.61329
2008	99.18891
2009	101.4336
2010	99.43286
2011	97.22521
2012	99.12482
2013	101.12906
2014	97.64132
2015	98.0536
2016	101.13231