Year	% of total
1990	33.3115513442583
1995	29.6178428488896
2000	24.4749646154105
2005	10.1724014195595
2010	11.888745618966
2011	31.4114283247379
2012	2.89436539181942
2013	2.23618986571746
2014	2.24550939546259
2015	2.02465674369929
2016	2.03428827818451
2017	2.04383779996992