Year	Percent
1996	9.9237
1997	10.5691
1998	13.5593
1999	17.6991
2000	15.7407
2001	14.7826
2002	15.7407
2003	17.5926
2004	13.9344
2005	11.1111
2006	8.6207
2007	9.0047
2008	7.6577
2009	9.8
2010	7.65
2011	6.97
2012	7.14
2013	5.49
2014	6.21
2015	5.7
2016	6.4935
2017	6.6532