Year	% of total
1990	91.5569994207148
1995	91.3108024749745
2000	92.47989079482
2005	86.4928441816598
2010	91.4012404737477
2011	91.3319562689092
2012	97.8053302151829
2013	94.6364496425382
2014	66.2885826772551
2015	99.7837146148697
2016	97.2965019200305
2017	98.3063737296891