Year	Percent
2000-01-01	15.900
2001-01-01	15.700
2002-01-01	15.475
2003-01-01	15.950
2004-01-01	16.100
2005-01-01	16.300
2006-01-01	16.075
2007-01-01	15.350
2008-01-01	14.700
2009-01-01	14.725
2010-01-01	16.275
2011-01-01	16.800
2012-01-01	16.075
2013-01-01	15.725
2014-01-01	15.825
2015-01-01	15.425
2016-01-01	15.650
2017-01-01	15.800