Year	%
1970	66.52063
1971	87.58113
1972	96.01035
1973	95.06604
1975	96.86898
1976	98.68001
1980	72.80265
1981	100
1982	99.81983
1983	95.31885
1987	88.01069
1988	85.78348
1991	87.42032
1992	89.40278
1995	92.15292
2000	92.58458
2001	96.89851
2002	98.00289
2005	95.52891
2006	95.44545
2007	95.99067
2008	98.46161
2009	99.45041
2010	96.68218
2011	96.38231
2012	93.81872
2013	92.99587
2014	93.72886
2015	92.78322
2016	92.43728
2017	95.2564