Year Percent 2003-01-01 84.825 2004-01-01 84.075 2005-01-01 85.525 2006-01-01 85.575 2007-01-01 85.425 2008-01-01 84.250 2009-01-01 83.275 2010-01-01 83.500 2011-01-01 83.775 2012-01-01 82.600 2013-01-01 83.850 2014-01-01 87.425 2015-01-01 87.550 2016-01-01 86.375 2017-01-01 85.400