Year	Percent
1996	4.04
1997	3.96
1998	3.79
1999	3.88
2000	3.31
2001	3.17
2002	3.26
2003	3.24
2004	3.02
2005	2.94
2006	2.97
2007	2.94
2008	2.86
2013	4.14