Year	Percent
2004	63.03684
2005	52.2215
2006	50.3713
2007	37.43397
2008	27.54043
2009	54.69056
2010	25.67837
2011	25.43375
2012	30.16774
2013	34.81411
2014	24.6195
2015	23.35704
2016	24.37907