Year	Percent
1998	3.41
1999	3.89
2000	2.47
2001	3.25
2002	2.93
2003	3.04
2004	2.04
2005	2.04
2006	1.59
2007	1.21
2008	1
2009	1.33
2010	1.44
2011	1.3
2012	1.15
2013	0.87
2014	1.16
2015	0.86
2016	0.74
2017	0.65