Year	Percent
2000-01-01	91.225
2001-01-01	91.425
2002-01-01	90.950
2003-01-01	89.525
2004-01-01	89.725
2005-01-01	89.925
2006-01-01	90.450
2007-01-01	90.825
2008-01-01	91.275
2009-01-01	90.850
2010-01-01	90.100
2011-01-01	89.600
2012-01-01	89.575
2013-01-01	89.050
2014-01-01	89.275
2015-01-01	89.025
2016-01-01	88.775
2017-01-01	87.850