Year	% of total
1990	96.5988056570257
1995	97.3715097425612
2000	99.0430801349789
2005	98.9039251750712
2010	97.1331214714452
2011	99.4928889972483
2012	96.9693931066147
2013	98.2732284682972
2014	64.0121987764943
2015	46.3740616669587
2016	24.1685615942642
2017	24.0200675197141