Year	Percent
2000-01-01	73.175
2001-01-01	74.300
2002-01-01	75.750
2003-01-01	77.050
2004-01-01	77.950
2005-01-01	78.975
2006-01-01	80.050
2007-01-01	81.200
2008-01-01	82.525
2009-01-01	83.025
2010-01-01	82.375
2011-01-01	81.800
2012-01-01	82.275
2013-01-01	82.575
2014-01-01	81.950
2015-01-01	82.150
2016-01-01	82.175
2017-01-01	82.025