Year Percent 2003-01-01 49.875 2004-01-01 49.675 2005-01-01 49.550 2006-01-01 49.475 2007-01-01 49.100 2008-01-01 48.900 2009-01-01 48.575 2010-01-01 48.550 2011-01-01 48.650 2012-01-01 48.475 2013-01-01 48.275 2014-01-01 48.375 2015-01-01 48.375 2016-01-01 48.375 2017-01-01 48.600