Year	Percent
1994	15.78015
1995	16.61887
1996	18.0282
1997	20.13312
1998	18.40759
1999	18.39019
2000	19.09717
2001	20.88993
2002	29.92158
2003	21.76326
2004	19.25308
2005	17.69436
2006	22.28167
2007	25.06375
2008	25.18123
2009	27.31246
2010	29.50673
2011	28.81677
2012	37.59611
2013	39.15536
2014	41.46445
2015	44.60729
2016	50.94713