Year	Percent
2000-01-01	58.625
2001-01-01	58.775
2002-01-01	58.800
2003-01-01	58.950
2004-01-01	59.150
2005-01-01	59.325
2006-01-01	59.325
2007-01-01	59.225
2008-01-01	59.225
2009-01-01	57.850
2010-01-01	57.500
2011-01-01	57.325
2012-01-01	57.575
2013-01-01	57.875
2014-01-01	58.850
2015-01-01	59.425
2016-01-01	59.900
2017-01-01	60.150