Year	Percent
1990	5.8
1995	2.4
1997	2.5
1999	2.8
2001	3.1
2002	2.9
2003	3.4
2004	4
2005	3.9
2006	3.6
2007	3.6
2008	4.1
2009	4
2010	3.8
2011	3.5
2012	4.2
2013	4.4
2014	4
2015	4.3
2016	4.5