Year	% of total
1990	54.2900621950157
1995	53.1127381039411
2000	49.8621920731902
2005	41.452538530279
2010	47.8996615677907
2011	51.7812853365591
2012	52.5961052272007
2013	50.895206016568
2014	50.0045377685398
2015	80.9038172504462
2016	74.2982925998685
2017	77.0061377963616