Year	Percent
1986	5.2
1989	13.4
1992	5.3
1996	4.9
1997	5.2
2000	5.5
2001	4
2002	6
2003	6.9
2004	8.8
2005	5.8
2006	4.5
2007	4.5
2008	3.8
2009	3.3
2010	2.6
2011	2.9
2012	2.7
2013	2.4
2014	2.3
2015	1.9
2016	1.6