Year	Percent
1998-01-01	65.200
1999-01-01	64.675
2000-01-01	64.225
2001-01-01	63.625
2002-01-01	63.225
2003-01-01	62.925
2004-01-01	61.450
2005-01-01	61.925
2006-01-01	61.800
2007-01-01	62.075
2008-01-01	61.350
2009-01-01	61.775
2010-01-01	61.850
2011-01-01	61.600
2012-01-01	60.300
2013-01-01	60.325
2014-01-01	59.900
2015-01-01	60.225
2016-01-01	59.550
2017-01-01	59.075