Quarter	Percent
1998-04-01	15.4
1998-10-01	13.4
1999-04-01	14.2
1999-10-01	15.4
2000-04-01	15.0
2000-10-01	15.5
2001-04-01	15.1
2001-10-01	14.4
2002-01-01	13.7
2002-04-01	14.9
2002-07-01	11.1
2002-10-01	13.2
2003-01-01	11.7
2003-04-01	12.1
2003-07-01	12.3
2003-10-01	10.3
2004-01-01	12.3
2004-04-01	11.2
2004-07-01	11.2
2004-10-01	11.4
2005-01-01	10.8
2005-04-01	10.9
2005-07-01	9.6
2005-10-01	9.0
2006-01-01	8.4
2006-04-01	8.0
2006-07-01	6.5
2006-10-01	6.4
2007-01-01	8.0
2007-04-01	6.6
2007-07-01	5.9
2007-10-01	5.6
2008-01-01	7.4
2008-04-01	6.6
2008-07-01	7.8
2008-10-01	11.7
2009-01-01	17.4
2009-04-01	20.8
2009-07-01	22.0
2009-10-01	23.6
2010-01-01	26.8
2010-04-01	23.8
2010-07-01	20.9
2010-10-01	19.4
2011-01-01	20.2
2011-04-01	20.2
2011-07-01	17.1
2011-10-01	17.1
2012-01-01	17.6
2012-04-01	17.4
2012-07-01	14.1
2012-10-01	15.6
2013-01-01	14.6
2013-04-01	12.1
2013-07-01	12.0
2013-10-01	11.8
2014-01-01	13.7
2014-04-01	12.2
2014-07-01	11.0
2014-10-01	10.4
2015-01-01	10.9
2015-04-01	11.4
2015-07-01	11.1
2015-10-01	11.0
2016-01-01	11.0
2016-04-01	10.6
2016-07-01	11.2
2016-10-01	10.7
2017-01-01	10.6
2017-04-01	10.4
2017-07-01	9.1
2017-10-01	9.0
2018-01-01	9.0
2018-04-01	9.2