Year	Percent
1996	6.1
1997	5.1
1998	5.2
1999	5.4
2000	5.4
2001	5.8
2002	6.3
2003	6.3
2004	6.2
2005	6.1
2006	6.3
2007	6.1
2008	6
2009	6.1
2010	5.6
2011	5.6
2012	6
2013	6.2
2014	6.4
2015	6.8
2016	6.7