Year	% of total
1990	90.2550221341339
1995	78.7803805412212
2000	70.162127482516
2005	68.4320979399694
2010	69.2836759242553
2011	74.4154732626865
2012	55.5912495476243
2013	48.2860657614945
2014	42.2594206035778
2015	48.5604338429968
2016	38.4146780038123
2017	42.3418302289266