Year	Percent
1994	14.101
1995	13.79
1996	12.681
1997	12.842
1998	12.5419
1999	15.9067
2000	18.6128
2001	18.5535
2002	18.7807
2003	17.2831
2004	19.6238
2005	17.2299
2006	14.7363
2007	12.6794
2008	10.9291
2009	12.8287
2010	14.5984
2011	13.6266
2012	14.5239
2013	14.5259
2014	13.6331
2015	12.8911
2016	10.7571
2017	8.4081