Year	Percent
2006	14.02182
2007	14.03129
2008	13.53335
2009	12.76891
2010	13.01602
2011	12.64582
2012	12.49393
2013	11.91267
2014	11.6235
2015	10.65844
2016	9.44153
2017	8.70091