Year	Percent
2005	19.88222
2006	21.68673
2007	21.39745
2008	20.30211
2009	18.94629
2010	19.68568
2011	20.30567
2012	20.47754
2013	19.75154
2014	19.7779
2015	19.93648
2016	19.95414