Year	Percent
1999-01-01	64.925
2000-01-01	65.100
2001-01-01	64.200
2002-01-01	64.775
2003-01-01	64.925
2004-01-01	65.900
2005-01-01	66.750
2006-01-01	66.525
2007-01-01	67.075
2008-01-01	67.125
2009-01-01	66.925
2010-01-01	67.650
2011-01-01	66.700
2012-01-01	66.925
2013-01-01	67.550
2014-01-01	67.700
2015-01-01	67.575
2016-01-01	67.625
2017-01-01	68.025