Year Percent 2003-01-01 3.100 2004-01-01 2.925 2005-01-01 2.475 2006-01-01 3.050 2007-01-01 2.275 2008-01-01 2.600 2009-01-01 5.675 2010-01-01 6.750 2011-01-01 6.175 2012-01-01 5.675 2013-01-01 5.075 2014-01-01 4.775 2015-01-01 4.025 2016-01-01 3.050 2017-01-01 2.725