Year	% of total
1990	58.5815517035505
1995	62.3105943368395
2000	65.6459564025439
2005	73.7797574587929
2010	67.1255999404763
2011	79.0027392323133
2012	66.5556593290971
2013	67.4163059835615
2014	30.3631187210679
2015	22.729662254522
2016	9.58302701276355
2017	8.8622212177093