Year	Percent
1999-01-01	91.950
2000-01-01	91.825
2001-01-01	91.050
2002-01-01	91.275
2003-01-01	90.900
2004-01-01	91.800
2005-01-01	92.175
2006-01-01	91.875
2007-01-01	92.475
2008-01-01	92.300
2009-01-01	91.800
2010-01-01	92.150
2011-01-01	90.650
2012-01-01	90.750
2013-01-01	90.850
2014-01-01	90.675
2015-01-01	89.875
2016-01-01	90.350
2017-01-01	90.050