Quarter	Percent
1998-01-01	3.6
1998-04-01	3.4
1998-07-01	3.3
1998-10-01	3.0
1999-01-01	2.9
1999-04-01	3.6
1999-07-01	2.9
1999-10-01	3.1
2000-01-01	3.4
2000-04-01	3.2
2000-07-01	2.9
2000-10-01	3.3
2001-01-01	3.1
2001-04-01	2.5
2001-07-01	3.5
2001-10-01	3.4
2002-01-01	3.5
2002-04-01	3.4
2002-07-01	3.7
2002-10-01	3.8
2003-01-01	3.5
2003-04-01	4.3
2003-07-01	4.1
2003-10-01	5.2
2004-01-01	4.6
2004-04-01	5.6
2004-07-01	5.9
2004-10-01	5.8
2005-01-01	5.6
2005-04-01	5.8
2005-07-01	6.5
2005-10-01	6.4
2006-01-01	6.6
2006-04-01	6.0
2006-07-01	5.9
2006-10-01	6.8
2007-01-01	6.4
2007-04-01	6.8
2007-07-01	6.2
2007-10-01	6.7
2008-01-01	7.2
2008-04-01	6.9
2008-07-01	6.0
2008-10-01	6.2
2009-01-01	6.7
2009-04-01	7.4
2009-07-01	8.6
2009-10-01	7.8
2010-01-01	8.7
2010-04-01	8.8
2010-07-01	9.0
2010-10-01	9.1
2011-01-01	10.1
2011-04-01	11.6
2011-07-01	10.7
2011-10-01	10.9
2012-01-01	11.6
2012-04-01	12.7
2012-07-01	12.5
2012-10-01	14.2
2013-01-01	14.1
2013-04-01	14.3
2013-07-01	13.2
2013-10-01	13.2
2014-01-01	13.7
2014-04-01	13.3
2014-07-01	12.6
2014-10-01	14.4
2015-01-01	14.1
2015-04-01	12.0
2015-07-01	12.0
2015-10-01	11.7
2016-01-01	11.7
2016-04-01	11.3
2016-07-01	10.1
2016-10-01	10.9
2017-01-01	10.0
2017-04-01	8.2
2017-07-01	8.2
2017-10-01	7.8
2018-01-01	7.6
2018-04-01	6.5