Year	Percent
1998-01-01	13.150
1999-01-01	16.400
2000-01-01	18.550
2001-01-01	18.750
2002-01-01	18.700
2003-01-01	17.775
2004-01-01	19.200
2005-01-01	17.225
2006-01-01	14.725
2007-01-01	12.675
2008-01-01	10.925
2009-01-01	12.825
2010-01-01	14.600
2011-01-01	13.650
2012-01-01	14.525
2013-01-01	14.500
2014-01-01	13.600
2015-01-01	12.900
2016-01-01	10.750
2017-01-01	8.400