Year	Percent
1998-01-01	5.325
1999-01-01	4.750
2000-01-01	4.250
2001-01-01	4.275
2002-01-01	5.275
2003-01-01	6.650
2004-01-01	7.025
2005-01-01	8.050
2006-01-01	8.125
2007-01-01	8.450
2008-01-01	8.025
2009-01-01	10.000
2010-01-01	11.400
2011-01-01	13.350
2012-01-01	16.325
2013-01-01	17.000
2014-01-01	14.475
2015-01-01	12.950
2016-01-01	11.525
2017-01-01	9.200