Year	Percent
1999-01-01	41.700
2000-01-01	41.300
2001-01-01	42.225
2002-01-01	42.375
2003-01-01	41.900
2004-01-01	42.100
2005-01-01	41.675
2006-01-01	41.050
2007-01-01	41.250
2008-01-01	41.875
2009-01-01	42.150
2010-01-01	42.175
2011-01-01	41.675
2012-01-01	40.750
2013-01-01	39.850
2014-01-01	38.150
2015-01-01	36.900
2016-01-01	35.650
2017-01-01	34.850