Year	%
1970	61.61498
1974	65.34278
1975	67.81239
1978	85.82221
1979	82.85973
1999	95.83134
2000	94.4274
2001	95.94675
2004	92.75099
2005	92.75072
2006	93.27881
2007	92.87041
2008	98.74651
2009	95.97794
2010	89.82081
2011	85.6142
2012	92.45543
2013	85.23767
2014	84.28493
2015	89.46872
2016	89.67384
2017	90.16632