Year	Percent
1998-01-01	10.950
1999-01-01	9.775
2000-01-01	9.075
2001-01-01	8.625
2002-01-01	9.125
2003-01-01	9.175
2004-01-01	8.750
2005-01-01	8.200
2006-01-01	7.375
2007-01-01	6.550
2008-01-01	6.050
2009-01-01	8.875
2010-01-01	9.100
2011-01-01	8.400
2012-01-01	8.275
2013-01-01	8.825
2014-01-01	9.300
2015-01-01	9.875
2016-01-01	9.025
2017-01-01	8.850