Year Percent 1999-01-01 3.475 2000-01-01 3.675 2001-01-01 3.750 2002-01-01 3.875 2003-01-01 2.900 2004-01-01 3.275 2005-01-01 4.225 2006-01-01 4.050 2007-01-01 4.750 2008-01-01 5.150 2009-01-01 6.650 2010-01-01 8.550 2011-01-01 10.050 2012-01-01 8.775 2013-01-01 8.575 2014-01-01 6.725 2015-01-01 5.950 2016-01-01 4.325 2017-01-01 3.025