Year	% of total
1990	88.3246230869651
1995	74.097591215989
2000	52.8222816826619
2005	30.1705701933973
2010	60.5147509774781
2011	52.1221186885419
2012	4.91903356391359
2013	0.217166101691402
2014	0.181258245765292
2015	0.201381024694758
2016	0.0426748923785025
2017	0.0425446030486443