Year	% of total
1990	98.949310925323
1995	97.9987515474104
2000	94.847622414999
2005	95.3345253506595
2010	92.2696364341085
2011	96.1070536471953
2012	84.497885512344
2013	82.0928108624709
2014	76.5562213320104
2015	78.3848263659879
2016	58.2649372359104
2017	62.7246772302731