Quarter	Percent
1998-04-01	14.5
1998-10-01	13.5
1999-04-01	13.8
1999-10-01	14.4
2000-04-01	14.2
2000-10-01	14.3
2001-04-01	13.9
2001-10-01	13.5
2002-01-01	13.2
2002-04-01	13.8
2002-07-01	10.9
2002-10-01	12.0
2003-01-01	11.8
2003-04-01	12.1
2003-07-01	11.8
2003-10-01	10.9
2004-01-01	12.3
2004-04-01	11.7
2004-07-01	11.2
2004-10-01	11.8
2005-01-01	11.6
2005-04-01	10.4
2005-07-01	9.5
2005-10-01	8.7
2006-01-01	8.6
2006-04-01	7.2
2006-07-01	6.0
2006-10-01	6.4
2007-01-01	7.1
2007-04-01	6.3
2007-07-01	5.6
2007-10-01	5.3
2008-01-01	6.7
2008-04-01	6.6
2008-07-01	7.4
2008-10-01	10.2
2009-01-01	14.2
2009-04-01	17.2
2009-07-01	18.8
2009-10-01	19.9
2010-01-01	21.3
2010-04-01	20.4
2010-07-01	18.5
2010-10-01	17.8
2011-01-01	17.6
2011-04-01	17.1
2011-07-01	15.1
2011-10-01	15.0
2012-01-01	16.3
2012-04-01	16.3
2012-07-01	13.7
2012-10-01	13.9
2013-01-01	13.0
2013-04-01	11.4
2013-07-01	11.8
2013-10-01	11.3
2014-01-01	11.9
2014-04-01	10.7
2014-07-01	10.6
2014-10-01	10.2
2015-01-01	10.2
2015-04-01	9.8
2015-07-01	9.7
2015-10-01	9.8
2016-01-01	10.3
2016-04-01	9.5
2016-07-01	9.5
2016-10-01	9.3
2017-01-01	9.4
2017-04-01	8.9
2017-07-01	8.5
2017-10-01	8.1
2018-01-01	8.2
2018-04-01	7.7