Quarter	Percent
1999-01-01	13.6
2000-01-01	13.6
2001-01-01	13.9
2002-01-01	13.9
2003-01-01	12.9
2003-04-01	13.2
2003-07-01	13.7
2003-10-01	13.0
2004-01-01	12.8
2004-04-01	12.8
2004-07-01	13.4
2004-10-01	12.6
2005-01-01	12.6
2005-04-01	12.8
2005-07-01	13.0
2005-10-01	12.5
2006-01-01	12.4
2006-04-01	12.6
2006-07-01	12.5
2006-10-01	12.2
2007-01-01	12.1
2007-04-01	12.1
2007-07-01	12.2
2007-10-01	11.8
2008-01-01	11.6
2008-04-01	11.4
2008-07-01	11.8
2008-10-01	11.2
2009-01-01	11.4
2009-04-01	11.2
2009-07-01	11.8
2009-10-01	11.2
2010-01-01	11.0
2010-04-01	11.3
2010-07-01	11.7
2010-10-01	11.3
2011-01-01	11.4
2011-04-01	11.8
2011-07-01	12.2
2011-10-01	11.6
2012-01-01	11.7
2012-04-01	11.7
2012-07-01	12.3
2012-10-01	11.6
2013-01-01	11.8
2013-04-01	11.6
2013-07-01	11.9
2013-10-01	11.5
2014-01-01	11.9
2014-04-01	12.2
2014-07-01	12.6
2014-10-01	11.9
2015-01-01	12.5
2015-04-01	12.6
2015-07-01	12.7
2015-10-01	12.3
2016-01-01	12.2
2016-04-01	12.6
2016-07-01	12.8
2016-10-01	12.4
2017-01-01	12.9
2017-04-01	12.4
2017-07-01	12.6
2017-10-01	12.4
2018-01-01	12.3
2018-04-01	12.2