Year	Percent
1993	13.9
1996	14.3
2004	14.3
2005	14.5
2006	14.5
2007	14.6
2008	14.6
2009	14.6
2010	14.5
2011	14.6
2012	14.5
2013	14.5
2014	14.6
2015	14.7