Year	% of total
1990	99.9583192746398
1995	99.9596668377058
2000	99.9667092095625
2005	99.931335517772
2010	99.9746344313873
2011	99.9934702173874
2012	99.9085935266891
2013	99.8562187902678
2014	99.7213348087994
2015	99.8345704823674
2016	99.6378371534564
2017	99.6629497098259