Year Percent 2001-01-01 69.125 2002-01-01 68.550 2003-01-01 67.900 2004-01-01 67.150 2005-01-01 67.725 2006-01-01 68.700 2007-01-01 69.650 2008-01-01 69.750 2009-01-01 67.175 2010-01-01 67.475 2011-01-01 68.125 2012-01-01 67.875 2013-01-01 68.175 2014-01-01 68.600 2015-01-01 68.800 2016-01-01 68.975 2017-01-01 69.925