Year Percent 2003-01-01 59.900 2004-01-01 61.200 2005-01-01 60.600 2006-01-01 61.100 2007-01-01 63.650 2008-01-01 60.375 2009-01-01 52.300 2010-01-01 51.200 2011-01-01 51.575 2012-01-01 51.675 2013-01-01 49.550 2014-01-01 47.925 2015-01-01 54.550 2016-01-01 50.900 2017-01-01 53.125