Year	Percent
1998-01-01	35.250
1999-01-01	35.125
2000-01-01	34.525
2001-01-01	33.925
2002-01-01	33.375
2003-01-01	33.300
2004-01-01	33.500
2005-01-01	33.075
2006-01-01	32.725
2007-01-01	32.450
2008-01-01	32.475
2009-01-01	32.950
2010-01-01	32.950
2011-01-01	33.300
2012-01-01	33.575
2013-01-01	34.200
2014-01-01	34.425
2015-01-01	34.475
2016-01-01	34.450
2017-01-01	33.800