Year	Percent
2002	15.87
2003	17.69
2004	21.78
2005	20.98
2006	19.27
2009	13.64
2010	12.88
2011	13.82
2012	14.53
2013	21.07
2014	20.7
2015	17.11
2016	14.36
2017	11.13