Year	Percent
1999	25.61794
2000	25.59424
2001	24.19167
2003	20.51761
2004	18.52856
2005	17.44801
2006	16.93339
2009	13.68972
2010	14.27735
2011	15.36192
2012	15.68077
2013	16.81842