Year	Percent
1998-01-01	44.225
1999-01-01	42.075
2000-01-01	41.700
2001-01-01	38.925
2002-01-01	38.850
2003-01-01	37.525
2004-01-01	39.700
2005-01-01	36.900
2006-01-01	35.725
2007-01-01	34.450
2008-01-01	34.000
2009-01-01	33.925
2010-01-01	33.025
2011-01-01	31.675
2012-01-01	31.250
2013-01-01	31.575
2014-01-01	29.975
2015-01-01	27.650
2016-01-01	26.425
2017-01-01	26.175