Year Percent 2005-01-01 45.475 2006-01-01 48.150 2007-01-01 51.300 2008-01-01 53.750 2009-01-01 56.075 2010-01-01 57.800 2011-01-01 60.025 2012-01-01 61.600 2013-01-01 63.600 2014-01-01 65.550 2015-01-01 66.175 2016-01-01 68.575 2017-01-01 70.150