Year Percent 1999-01-01 62.850 2000-01-01 63.625 2001-01-01 64.200 2002-01-01 64.125 2003-01-01 63.075 2004-01-01 63.975 2005-01-01 64.125 2006-01-01 65.250 2007-01-01 65.000 2008-01-01 65.500 2009-01-01 64.050 2010-01-01 62.350 2011-01-01 61.525 2012-01-01 60.950 2013-01-01 60.600 2014-01-01 60.425 2015-01-01 60.475 2016-01-01 62.150 2017-01-01 61.475