Year Percent 2005-01-01 38.275 2006-01-01 37.800 2007-01-01 37.425 2008-01-01 37.025 2009-01-01 36.950 2010-01-01 36.950 2011-01-01 36.775 2012-01-01 36.375 2013-01-01 36.300 2014-01-01 36.300 2015-01-01 36.225 2016-01-01 35.875 2017-01-01 35.775