Year	Percent
1998	11.5
1999	10.4
2000	7.1
2001	3.2
2002	2
2003	1.4
2004	0.3
2005	0.4
2006	0.1
2007	0.1
2008	0
2009	0
2010	0
2011	0
2012	0
2013	0
2014	0
2015	0
2016	0