Year	Percent
2002	14.27
2004	9.26
2005	9.05
2006	9.03
2008	9.38
2009	9.76
2010	9.94
2011	9.85
2012	9.47
2013	9.66
2014	9.49
2015	9.02
2016	8.74
2017	8.91