Year	Percent
2001-01-01	75.725
2002-01-01	74.950
2003-01-01	74.250
2004-01-01	73.600
2005-01-01	74.300
2006-01-01	75.475
2007-01-01	76.550
2008-01-01	76.750
2009-01-01	74.175
2010-01-01	74.550
2011-01-01	75.775
2012-01-01	75.625
2013-01-01	76.300
2014-01-01	76.550
2015-01-01	77.000
2016-01-01	77.525
2017-01-01	78.250