Year Percent 2005-01-01 66.1 2006-01-01 66.5 2007-01-01 66.7 2008-01-01 66.3 2009-01-01 63.9 2010-01-01 63.6 2011-01-01 63.8 2012-01-01 63.7 2013-01-01 63.5 2014-01-01 63.8 2015-01-01 64.1 2016-01-01 64.5