Year	Percent
1999-01-01	62.325
2000-01-01	62.500
2001-01-01	62.875
2002-01-01	62.525
2003-01-01	61.950
2004-01-01	62.400
2005-01-01	62.475
2006-01-01	63.350
2007-01-01	63.200
2008-01-01	63.725
2009-01-01	61.400
2010-01-01	59.575
2011-01-01	59.100
2012-01-01	58.400
2013-01-01	58.000
2014-01-01	58.100
2015-01-01	58.375
2016-01-01	59.625
2017-01-01	58.700