Year	Percent
1999-01-01	59.550
2000-01-01	59.625
2001-01-01	60.125
2002-01-01	61.250
2003-01-01	61.575
2004-01-01	59.750
2005-01-01	61.100
2006-01-01	62.225
2007-01-01	63.475
2008-01-01	64.825
2009-01-01	65.200
2010-01-01	65.650
2011-01-01	66.075
2012-01-01	66.625
2013-01-01	66.850
2014-01-01	66.925
2015-01-01	67.100
2016-01-01	67.650
2017-01-01	68.175