Year Percent 1999-01-01 68.050 2000-01-01 68.375 2001-01-01 68.800 2002-01-01 68.600 2003-01-01 68.050 2004-01-01 68.525 2005-01-01 68.575 2006-01-01 69.600 2007-01-01 69.250 2008-01-01 69.775 2009-01-01 67.200 2010-01-01 65.200 2011-01-01 64.725 2012-01-01 64.050 2013-01-01 63.625 2014-01-01 63.800 2015-01-01 64.225 2016-01-01 65.750 2017-01-01 64.850