Year	Percent
2005-01-01	56.6
2006-01-01	55.4
2007-01-01	54.6
2008-01-01	54.0
2009-01-01	52.9
2010-01-01	52.1
2011-01-01	51.4
2012-01-01	50.4
2013-01-01	49.4
2014-01-01	48.5
2015-01-01	47.7
2016-01-01	46.7