Year	Percent
1999-01-01	7.575
2000-01-01	7.050
2001-01-01	6.350
2002-01-01	6.150
2003-01-01	6.100
2004-01-01	6.075
2005-01-01	6.975
2006-01-01	7.150
2007-01-01	7.175
2008-01-01	7.675
2009-01-01	10.275
2010-01-01	11.625
2011-01-01	11.075
2012-01-01	11.350
2013-01-01	10.225
2014-01-01	7.575
2015-01-01	6.600
2016-01-01	5.150
2017-01-01	3.825