Year	Percent
1999-01-01	63.875
2000-01-01	60.300
2001-01-01	59.250
2002-01-01	59.875
2003-01-01	60.275
2004-01-01	60.475
2005-01-01	61.975
2006-01-01	61.875
2007-01-01	62.875
2008-01-01	62.875
2009-01-01	62.875
2010-01-01	62.625
2011-01-01	63.650
2012-01-01	63.150
2013-01-01	62.275
2014-01-01	60.700
2015-01-01	60.700
2016-01-01	60.225
2017-01-01	58.425