Year	Percent
1998-01-01	4.550
1999-01-01	4.150
2000-01-01	3.550
2001-01-01	3.500
2002-01-01	4.450
2003-01-01	5.800
2004-01-01	6.025
2005-01-01	7.225
2006-01-01	7.350
2007-01-01	7.750
2008-01-01	7.225
2009-01-01	9.250
2010-01-01	10.675
2011-01-01	11.925
2012-01-01	14.700
2013-01-01	15.500
2014-01-01	12.700
2015-01-01	11.200
2016-01-01	10.025
2017-01-01	7.900