Year	Percent
1996	13.12
1997	13.33
1998	12.5
2006	12.38
2007	11.44
2009	13.97
2010	10.27
2011	8.62
2012	8.62
2013	8.7
2014	9.89
2015	8.92
2016	9.8
2017	10.06
2018	9.61
2019	9.95