Year	% of total
1990	98.9555293778863
1995	98.9596841005698
2000	99.4155451056111
2005	99.4615826703709
2010	99.4752399807101
2011	99.4888371909229
2012	99.5043746577279
2013	99.5191685779464
2014	99.5316144265572
2015	99.5407926871615
2016	99.5463762823383
2017	99.5492069858699