Year	Percent
2001-01-01	79.925
2002-01-01	79.375
2003-01-01	79.150
2004-01-01	79.150
2005-01-01	80.525
2006-01-01	81.150
2007-01-01	81.400
2008-01-01	81.675
2009-01-01	81.375
2010-01-01	81.900
2011-01-01	82.425
2012-01-01	82.600
2013-01-01	83.350
2014-01-01	83.625
2015-01-01	83.525
2016-01-01	83.900
2017-01-01	84.300