Year	Percent
2000-01-01	85.350
2001-01-01	85.150
2002-01-01	84.625
2003-01-01	83.025
2004-01-01	83.125
2005-01-01	83.250
2006-01-01	84.375
2007-01-01	85.725
2008-01-01	86.775
2009-01-01	85.950
2010-01-01	84.700
2011-01-01	84.675
2012-01-01	84.575
2013-01-01	84.075
2014-01-01	83.900
2015-01-01	83.075
2016-01-01	82.650
2017-01-01	82.450