Year	Percent
1999-01-01	10.975
2000-01-01	11.225
2001-01-01	8.300
2002-01-01	10.075
2003-01-01	9.375
2004-01-01	9.425
2005-01-01	7.525
2006-01-01	7.300
2007-01-01	7.725
2008-01-01	8.950
2009-01-01	13.275
2010-01-01	13.900
2011-01-01	14.675
2012-01-01	17.900
2013-01-01	19.675
2014-01-01	19.425
2015-01-01	18.700
2016-01-01	17.275
2017-01-01	15.925