Year	Percent
2004	15.31041
2005	13.88488
2006	14.81059
2007	16.19505
2008	14.90892
2009	15.33884
2010	15.70321
2011	16.4438
2012	16.60055
2013	20.01714
2015	21.7928
2016	21.93499