Year	% of total
1990	56.7002806148474
1995	56.7185305470212
2000	60.3738485562067
2005	62.902792807344
2010	68.3474073464344
2011	70.3987223034097
2012	68.598086793634
2013	63.2135688297831
2014	60.5433333223404
2015	64.9002263521275
2016	62.0379781155043
2017	63.2975280950531