Year	Percent
1999-01-01	48.100
2000-01-01	47.050
2001-01-01	47.675
2002-01-01	46.100
2003-01-01	44.850
2004-01-01	43.975
2005-01-01	42.875
2006-01-01	42.050
2007-01-01	41.425
2008-01-01	40.625
2009-01-01	40.500
2010-01-01	40.400
2011-01-01	40.325
2012-01-01	40.225
2013-01-01	40.625
2014-01-01	41.050
2015-01-01	41.175
2016-01-01	41.475
2017-01-01	41.875