Year	%
1970	91.95038
1971	91.96055
1972	89.91431
1973	89.09581
1974	87.3777
1975	85.77748
1976	91.72373
1982	94.08738
1996	97.96823
2010	95.69367
2011	96.68376
2012	96.45688
2013	96.70423
2014	96.74968
2015	96.98251
2016	97.39707