Year	% of total
1990	99.8551980142721
1995	99.8548979310268
2000	99.7834042709106
2005	78.9402225446508
2010	33.7810509576137
2011	88.9096640301876
2012	91.5317084280487
2013	57.2198327860564
2014	35.9664749860667
2015	99.5307870049802
2016	99.3447921105032
2017	99.3509980193392