Year	% of total
1990	100
1995	100
2000	100
2005	99.1570035998759
2010	98.4824793226902
2011	99.9718935172555
2012	99.9748065595616
2013	98.4688663509987
2014	99.0458111157343
2015	100
2016	100
2017	100