Year	Percent
2006-01-01	14.825
2007-01-01	14.675
2008-01-01	14.825
2009-01-01	16.025
2010-01-01	17.050
2011-01-01	17.875
2012-01-01	17.950
2013-01-01	18.250
2014-01-01	17.450
2015-01-01	17.700
2016-01-01	18.100
2017-01-01	18.650