Year	Percent
1993	10.8
1996	11.3
1997	5.6
1998	7.9
1999	13.3
2000	10
2001	6.6
2002	4.7
2003	4.8
2004	4.1
2005	3.2
2006	2.2
2007	1.3
2008	0.5
2009	0.5
2010	0.5
2011	0.3
2012	0.3
2013	0.3
2014	0.2
2015	0.3