Year	Percent
1998-01-01	8.50000
1999-01-01	9.20000
2000-01-01	9.80000
2001-01-01	10.50000
2002-01-01	11.90000
2003-01-01	12.10000
2004-01-01	11.50000
2005-01-01	11.30000
2006-01-01	10.00000
2007-01-01	9.00000
2008-01-01	9.30000
2009-01-01	8.70000
2010-01-01	8.43702
2011-01-01	8.43324
2012-01-01	8.60000
2013-01-01	8.20000
2014-01-01	7.90000
2015-01-01	7.70000