Year Percent 2005-01-01 43.925 2006-01-01 43.900 2007-01-01 44.375 2008-01-01 44.400 2009-01-01 43.525 2010-01-01 42.250 2011-01-01 41.875 2012-01-01 41.450 2013-01-01 41.000 2014-01-01 40.125 2015-01-01 39.725 2016-01-01 39.650 2017-01-01 39.775