Year	% of total
1992	26.731898550724637
1993	24.047685459940656
1994	12.596564885496184
1995	30.37232608695652
1996	26.755753899480066
1997	29.452003514938486
1998	28.338673300165834
1999	29.473799582463467
2000	25.83389721627409
2001	27.340856423173804
2002	20.21645875251509
2003	22.30375670840787
2004	27.766312949640287
2005	25.87656603773585
2006	23.91821428571429
2007	34.57295208655332
2008	32.27545938748336
2009	46.217218934911244
2010	43.426519685039366
2011	47.78649606299213
2012	46.47539761431412
2013	51.17380597014925
2014	45.3559938208033
2015	47.09613437195716
2016	52.73675257731959