Year	Percent
1992	7.901
1993	6.703
1994	7.485
1995	6.682
1996	6.314
1997	5.4343
1998	5.4951
1999	8.5097
2000	9.1244
2001	10.6905
2002	11.9766
2003	10.8056
2004	11.8683
2005	12.1758
2006	9.7558
2007	7.3849
2008	5.7641
2009	6.6975
2010	7.5234
2011	7.3562
2012	7.9813
2013	8.2926
2014	7.1314
2015	5.9001
2016	5.0507
2017	4.1143