Year	Percent
1998-01-01	6.325
1999-01-01	5.275
2000-01-01	5.050
2001-01-01	5.100
2002-01-01	6.125
2003-01-01	7.350
2004-01-01	7.675
2005-01-01	8.725
2006-01-01	9.050
2007-01-01	9.650
2008-01-01	8.900
2009-01-01	10.275
2010-01-01	12.050
2011-01-01	13.200
2012-01-01	15.700
2013-01-01	16.575
2014-01-01	14.475
2015-01-01	12.825
2016-01-01	11.225
2017-01-01	9.425