Year Percent 2005-01-01 30.100 2006-01-01 29.600 2007-01-01 29.200 2008-01-01 28.775 2009-01-01 28.675 2010-01-01 28.675 2011-01-01 28.550 2012-01-01 28.025 2013-01-01 27.825 2014-01-01 27.675 2015-01-01 27.525 2016-01-01 27.175 2017-01-01 26.925