Year	Percent
1999-01-01	6.150
2000-01-01	5.575
2001-01-01	4.950
2002-01-01	5.350
2003-01-01	5.700
2004-01-01	5.375
2005-01-01	5.625
2006-01-01	5.425
2007-01-01	4.450
2008-01-01	3.700
2009-01-01	5.350
2010-01-01	6.975
2011-01-01	7.800
2012-01-01	8.250
2013-01-01	9.700
2014-01-01	9.300
2015-01-01	8.675
2016-01-01	7.725
2017-01-01	6.250