Year	Percent
1998-01-01	3.575
1999-01-01	3.550
2000-01-01	2.750
2001-01-01	2.625
2002-01-01	3.525
2003-01-01	4.900
2004-01-01	5.125
2005-01-01	6.150
2006-01-01	5.850
2007-01-01	6.100
2008-01-01	5.975
2009-01-01	8.475
2010-01-01	9.275
2011-01-01	11.525
2012-01-01	14.650
2013-01-01	15.425
2014-01-01	12.050
2015-01-01	10.800
2016-01-01	9.675
2017-01-01	7.275