Year	Percent
2003	17.8778
2004	16.44976
2005	16.94567
2006	16.24525
2007	14.33132
2008	14.72918
2009	11.5861
2010	13.39821
2011	14.5808
2012	16.1929
2013	15.02702
2014	17.33559
2015	17.03779
2016	18.41174
2017	19.05688
2018	18.43015
2019	18.47637
2020	17.44634
2021	17.48632