Year	Percent
1999-01-01	16.575
2000-01-01	15.800
2001-01-01	15.325
2002-01-01	15.100
2003-01-01	15.650
2004-01-01	13.825
2005-01-01	13.575
2006-01-01	13.025
2007-01-01	12.700
2008-01-01	11.475
2009-01-01	12.075
2010-01-01	11.900
2011-01-01	11.625
2012-01-01	10.925
2013-01-01	11.325
2014-01-01	11.725
2015-01-01	11.425
2016-01-01	11.100
2017-01-01	9.725