Year	Percent
1998-01-01	11.900
1999-01-01	11.000
2000-01-01	10.600
2001-01-01	9.600
2002-01-01	9.800
2003-01-01	9.800
2004-01-01	9.900
2005-01-01	9.700
2006-01-01	8.975
2007-01-01	7.825
2008-01-01	7.475
2009-01-01	8.825
2010-01-01	9.500
2011-01-01	9.725
2012-01-01	10.500
2013-01-01	10.875
2014-01-01	10.375
2015-01-01	9.525
2016-01-01	8.775
2017-01-01	7.900