Year	Percent
1996	3.11
1997	2.94
1998	2.85
1999	2.82
2000	2.5
2001	2.58
2002	2.57
2003	2.35
2004	2.04
2005	2.04
2006	2.21
2007	2.36
2008	1.96
2009	2.19
2010	2.02
2011	2.14
2012	2.07
2013	2.15
2014	2.05
2015	1.97
2016	1.99
2017	2.05