Year	% of total
1990	99.9965611905267
1995	99.9895428699905
2000	99.9978583189942
2005	99.9950209632121
2010	99.9964541233472
2011	99.9980154373594
2012	99.9896708694634
2013	99.9949191371602
2014	98.8696968734355
2015	99.6283792584814
2016	97.4777979711542
2017	97.6814356621289