Year	% of total
1990	70.961562052102
1995	55.4619531865773
2000	53.0794718637485
2005	56.9833347015064
2010	52.0533754614002
2011	55.154591692984
2012	39.8091363973099
2013	36.274820003323
2014	23.5264102900366
2015	25.8846294586363
2016	8.64998741448497
2017	14.137165929715