Year Percent 2005-01-01 62.900 2006-01-01 63.700 2007-01-01 63.900 2008-01-01 65.700 2009-01-01 65.700 2010-01-01 63.650 2011-01-01 64.625 2012-01-01 64.950 2013-01-01 65.175 2014-01-01 65.925 2015-01-01 66.350 2016-01-01 66.975 2017-01-01 66.700