Year	Percent
2005-01-01	13.5
2006-01-01	12.6
2007-01-01	12.0
2008-01-01	12.9
2009-01-01	16.7
2010-01-01	16.9
2011-01-01	16.4
2012-01-01	16.4
2013-01-01	16.2
2014-01-01	15.1
2015-01-01	13.9
2016-01-01	13.0