Year	Percent
1998-01-01	37.350
1999-01-01	37.500
2000-01-01	36.175
2001-01-01	33.875
2002-01-01	33.175
2003-01-01	31.200
2004-01-01	33.425
2005-01-01	30.450
2006-01-01	28.600
2007-01-01	27.500
2008-01-01	26.075
2009-01-01	27.400
2010-01-01	27.050
2011-01-01	26.575
2012-01-01	27.025
2013-01-01	25.275
2014-01-01	26.075
2015-01-01	24.300
2016-01-01	22.875
2017-01-01	23.925