Year	Percent
2001-01-01	77.850
2002-01-01	77.600
2003-01-01	77.325
2004-01-01	77.175
2005-01-01	78.225
2006-01-01	78.775
2007-01-01	79.150
2008-01-01	79.350
2009-01-01	78.925
2010-01-01	79.100
2011-01-01	79.925
2012-01-01	80.300
2013-01-01	81.100
2014-01-01	81.525
2015-01-01	81.750
2016-01-01	82.100
2017-01-01	82.525