Year	Percent
1999-01-01	6.6
2000-01-01	6.2
2001-01-01	6.4
2002-01-01	6.9
2003-01-01	7.1
2004-01-01	6.9
2005-01-01	6.6
2006-01-01	6.1
2007-01-01	5.6
2008-01-01	6.0
2009-01-01	8.1
2010-01-01	8.3
2011-01-01	8.0
2012-01-01	8.0
2013-01-01	7.9
2014-01-01	7.4
2015-01-01	6.8
2016-01-01	6.3