Year	Percent
1994	11.628
1995	12.047
1996	11.067
1997	11.016
1998	11.2071
1999	13.1299
2000	16.0034
2001	15.8571
2002	15.7696
2003	15.3037
2004	18.1402
2005	15.7943
2006	13.5079
2007	12.0231
2008	10.2086
2009	11.7612
2010	13.3197
2011	12.5173
2012	13.4396
2013	13.6036
2014	12.6761
2015	12.1733
2016	9.8153
2017	7.9526