Year Percent 2000-01-01 46.550 2001-01-01 45.475 2002-01-01 44.475 2003-01-01 44.400 2004-01-01 44.675 2005-01-01 45.900 2006-01-01 46.450 2007-01-01 59.125 2008-01-01 55.650 2009-01-01 47.725 2010-01-01 40.875 2011-01-01 38.175 2012-01-01 37.200 2013-01-01 37.200 2014-01-01 36.775 2015-01-01 37.275 2016-01-01 41.825 2017-01-01 39.750