Year	Percent
1999-01-01	41.225
2000-01-01	41.550
2001-01-01	41.425
2002-01-01	41.050
2003-01-01	40.525
2004-01-01	42.075
2005-01-01	41.425
2006-01-01	40.925
2007-01-01	40.075
2008-01-01	39.825
2009-01-01	39.575
2010-01-01	39.600
2011-01-01	39.525
2012-01-01	39.250
2013-01-01	39.075
2014-01-01	39.325
2015-01-01	39.250
2016-01-01	38.775
2017-01-01	38.800