Year	% of total
1992	61.75175800711743
1993	33.03467142320691
1994	26.830346820809247
1995	24.285785222853725
1996	31.75431795217245
1997	30.778794255177022
1998	38.63596273291925
1999	36.10616158792284
2000	33.50553324287653
2001	30.807035967445522
2002	33.20605863192183
2003	33.7304548525107
2004	32.80093122597181
2005	31.78673283705542
2006	30.181039613915146
2007	27.920094306049826
2008	28.523261213720318
2009	30.301153235410876
2010	29.637747559274757
2011	28.0186327077748
2012	28.04176470588235
2013	28.192294187075834
2014	28.77558065908764
2015	27.924754439511656
2016	27.74944459872258