Year	Percent
2005-01-01	64.8
2006-01-01	65.7
2007-01-01	66.3
2008-01-01	66.7
2009-01-01	65.9
2010-01-01	65.8
2011-01-01	66.1
2012-01-01	66.3
2013-01-01	66.5
2014-01-01	66.9
2015-01-01	67.4
2016-01-01	68.1