Year	Percent
2000-01-01	83.700
2001-01-01	84.275
2002-01-01	84.775
2003-01-01	85.350
2004-01-01	85.950
2005-01-01	86.450
2006-01-01	87.125
2007-01-01	87.650
2008-01-01	88.550
2009-01-01	88.775
2010-01-01	87.875
2011-01-01	87.400
2012-01-01	87.675
2013-01-01	87.425
2014-01-01	87.075
2015-01-01	87.100
2016-01-01	86.925
2017-01-01	86.700