Year Percent 2005-01-01 70.0 2006-01-01 70.3 2007-01-01 70.4 2008-01-01 70.6 2009-01-01 70.5 2010-01-01 70.4 2011-01-01 70.5 2012-01-01 70.7 2013-01-01 70.9 2014-01-01 71.0 2015-01-01 71.2 2016-01-01 71.6