Year	Percent
1998-01-01	26.500
1999-01-01	26.725
2000-01-01	27.350
2001-01-01	27.750
2002-01-01	27.625
2003-01-01	28.200
2004-01-01	28.250
2005-01-01	27.775
2006-01-01	27.825
2007-01-01	27.825
2008-01-01	28.025
2009-01-01	27.825
2010-01-01	28.025
2011-01-01	28.425
2012-01-01	28.150
2013-01-01	27.600
2014-01-01	27.450
2015-01-01	27.550
2016-01-01	26.900
2017-01-01	26.625