Year	% of total
1990	100
1995	99.7870110030077
2000	99.4832169595754
2005	99.9506672127325
2010	99.5296320730183
2011	99.6634065169497
2012	92.3374796288633
2013	83.9850247909386
2014	67.3514721473491
2015	84.6299028317521
2016	58.5599377023401
2017	58.7812110818322