Year	Percent
1999-01-01	61.475
2000-01-01	61.525
2001-01-01	60.925
2002-01-01	60.850
2003-01-01	60.525
2004-01-01	61.125
2005-01-01	61.375
2006-01-01	60.850
2007-01-01	61.075
2008-01-01	60.850
2009-01-01	60.375
2010-01-01	60.775
2011-01-01	59.700
2012-01-01	59.750
2013-01-01	59.675
2014-01-01	59.250
2015-01-01	58.900
2016-01-01	58.725
2017-01-01	59.150