Year	Percent
1998-01-01	6.875
1999-01-01	7.075
2000-01-01	7.475
2001-01-01	7.375
2002-01-01	7.475
2003-01-01	7.600
2004-01-01	7.675
2005-01-01	7.525
2006-01-01	7.100
2007-01-01	7.100
2008-01-01	6.800
2009-01-01	7.500
2010-01-01	7.325
2011-01-01	7.550
2012-01-01	7.850
2013-01-01	8.850
2014-01-01	8.400
2015-01-01	8.250
2016-01-01	8.100
2017-01-01	7.650