Year	% of total
1990	54.92600193820738
1991	65.58603470964586
1992	68.47743336808657
1993	72.06436120792793
1994	68.66730201608075
1995	63.83250864873981
1996	61.020581645109274
1997	58.00530021196172
1998	59.95515035109282
1999	60.422975407149046
2000	70.18587163279581
2001	66.22068393324179
2002	61.356213745783016
2003	66.30902518769415
2004	68.1431181328394
2005	62.162780561794904
2006	62.39918940037549
2007	56.480783419558925
2008	58.00139826346244
2009	60.15084938949551
2010	58.295826355710545
2011	55.73888813982701
2012	58.882100513407835
2013	56.67017674947749
2014	57.826596123906896
2015	53.610519965172465
2016	49.14760709483969