Year	Percent
1999-01-01	6.700
2000-01-01	6.175
2001-01-01	5.700
2002-01-01	5.475
2003-01-01	5.550
2004-01-01	5.300
2005-01-01	6.050
2006-01-01	6.400
2007-01-01	6.475
2008-01-01	6.950
2009-01-01	9.250
2010-01-01	10.675
2011-01-01	9.925
2012-01-01	10.275
2013-01-01	9.075
2014-01-01	6.475
2015-01-01	5.600
2016-01-01	4.500
2017-01-01	3.400