Quarter	Percent
1999-04-01	12.4
1999-07-01	14.6
1999-10-01	12.6
2000-01-01	12.3
2000-04-01	12
2000-07-01	13.6
2000-10-01	12.6
2001-01-01	11.7
2001-04-01	10.3
2001-07-01	12.9
2001-10-01	12.2
2002-01-01	11.5
2002-04-01	10.9
2002-07-01	13.3
2002-10-01	12.2
2003-01-01	11.9
2003-04-01	11.4
2003-07-01	13.8
2003-10-01	11.8
2004-01-01	11.2
2004-04-01	10.7
2004-07-01	13.5
2004-10-01	12.4
2005-01-01	11.9
2005-04-01	11.6
2005-07-01	13.7
2005-10-01	13.7
2006-01-01	12.9
2006-04-01	13.6
2006-07-01	15.5
2006-10-01	13.5
2007-01-01	14
2007-04-01	14.1
2007-07-01	15.6
2007-10-01	13.3
2008-01-01	13.3
2008-04-01	13.9
2008-07-01	16.7
2008-10-01	16
2009-01-01	17.5
2009-04-01	18.8
2009-07-01	21
2009-10-01	19.1
2010-01-01	19.7
2010-04-01	19.2
2010-07-01	20.3
2010-10-01	20.3
2011-01-01	19.8
2011-04-01	20.2
2011-07-01	23.1
2011-10-01	21.9
2012-01-01	21.6
2012-04-01	20.9
2012-07-01	21.7
2012-10-01	20.6
2013-01-01	20.2
2013-04-01	20.9
2013-07-01	21.9
2013-10-01	19.6
2014-01-01	18.4
2014-04-01	16.1
2014-07-01	17.3
2014-10-01	16
2015-01-01	15.2
2015-04-01	15.0
2015-07-01	15.2
2015-10-01	13.1
2016-01-01	13.0
2016-04-01	12.9
2016-07-01	14.0
2016-10-01	12.1
2017-01-01	11.9
2017-04-01	11.6
2017-07-01	13.0
2017-10-01	11.8
2018-01-01	11.5
2018-04-01	10.6