Year	Percent
2000-01-01	24.550
2001-01-01	24.725
2002-01-01	24.700
2003-01-01	24.725
2004-01-01	24.725
2005-01-01	24.625
2006-01-01	24.300
2007-01-01	24.500
2008-01-01	24.200
2009-01-01	24.350
2010-01-01	24.625
2011-01-01	24.500
2012-01-01	23.950
2013-01-01	23.575
2014-01-01	23.300
2015-01-01	23.100
2016-01-01	22.700
2017-01-01	22.425