Year Percent 2000-01-01 70.550 2001-01-01 70.725 2002-01-01 70.500 2003-01-01 70.750 2004-01-01 70.850 2005-01-01 70.825 2006-01-01 70.825 2007-01-01 70.925 2008-01-01 70.725 2009-01-01 68.375 2010-01-01 67.975 2011-01-01 67.775 2012-01-01 68.200 2013-01-01 68.525 2014-01-01 69.575 2015-01-01 70.225 2016-01-01 70.750 2017-01-01 70.875