Year	Percent
2001-01-01	24.275
2002-01-01	24.250
2003-01-01	24.600
2004-01-01	24.850
2005-01-01	24.150
2006-01-01	23.725
2007-01-01	23.225
2008-01-01	23.075
2009-01-01	23.600
2010-01-01	23.775
2011-01-01	22.650
2012-01-01	22.075
2013-01-01	21.250
2014-01-01	20.700
2015-01-01	20.100
2016-01-01	19.825
2017-01-01	19.350