Year	Percent
2005-01-01	13.2
2006-01-01	12.5
2007-01-01	11.7
2008-01-01	12.3
2009-01-01	15.2
2010-01-01	15.8
2011-01-01	15.8
2012-01-01	15.8
2013-01-01	15.7
2014-01-01	14.6
2015-01-01	13.4
2016-01-01	12.5