Year	% of total
1990	86.97226415045185
1991	94.72674362511235
1992	83.12430716922646
1993	87.74701598588803
1994	86.41070094148887
1995	86.38464384733449
1996	84.10778826000457
1997	82.36650709701442
1998	79.29446954575654
1999	79.2830472048004
2000	76.97086602217195
2001	76.79401466394714
2002	68.56284218064836
2003	76.06710204857347
2004	75.03070618266105
2005	69.5636491109829
2006	69.80745339122059
2007	73.47665403024226
2008	72.44943340470692
2009	68.40879843081025
2010	66.69769847858224
2011	66.07394999967325
2012	63.543222339180154
2013	65.95371708101679
2014	65.53223140283175
2015	61.39582449196326
2016	60.60622375016106