Year	Percent
2006	26.26911
2007	23.74311
2008	22.11639
2009	37.92639
2010	35.75247
2011	29.41166
2012	35.32865
2013	29.42683
2014	20.71446
2015	16.27812
2016	9.78021
2017	21.89897
2018	14.84843