Year	% of total
1990	7.42661664091812
1991	4.719829996644671
1992	7.863401482812852
1993	4.841070681723129
1994	1.151259546335347
1995	2.608883139284174
1996	1.0740177212924014
1997	4.9916967861678225
1998	4.697049065828531
1999	3.9762657008553597
2000	13.770753795613958
2001	12.825933756166313
2002	16.599763872491145
2003	18.223165554881746
2004	15.391811182269555
2005	17.829516734318755
2006	17.464984910624466
2007	19.314467915504185
2008	19.52116422815116
2009	12.400897531787585
2010	16.119221411192214
2011	22.963358235503378
2012	21.127159444916455
2013	17.358571735857172
2014	17.62429294432867
2015	20.5552589428724