Year	% of total
1990	63.20440781126853
1991	64.77544208096121
1992	65.88563392480611
1993	68.59100518331104
1994	68.35882659335499
1995	71.59631170700204
1996	74.52409051552915
1997	68.68653378442099
1998	66.47947632768698
1999	70.92484588918305
2000	73.49036200743407
2001	70.38213743702516
2002	64.89390229743401
2003	64.3693248845145
2004	61.1303804209453
2005	58.588338860692716
2006	55.988431880145136
2007	54.47313795528058
2008	61.82389613021038
2009	44.45322906333373
2010	57.31524036403662
2011	52.82953675565796
2012	49.378754901925284
2013	55.5142426749777
2014	52.29208484172543
2015	53.36119104743876
2016	61.7404357642008