Quarter	Percent
1998-01-01	10.0
1998-04-01	9.3
1998-07-01	13.1
1998-10-01	14.5
1999-01-01	18
1999-04-01	16.3
1999-07-01	17.5
1999-10-01	19
2000-01-01	19.6
2000-04-01	17.4
2000-07-01	18.5
2000-10-01	19.3
2001-01-01	18.5
2001-04-01	16.4
2001-07-01	18.6
2001-10-01	17.9
2002-01-01	18.4
2002-04-01	15.7
2002-07-01	16.8
2002-10-01	15.4
2003-01-01	16.6
2003-04-01	16.2
2003-07-01	19.6
2003-10-01	20.9
2004-01-01	22.3
2004-04-01	21.4
2004-07-01	22.4
2004-10-01	22.7
2005-01-01	23.3
2005-04-01	17.6
2005-07-01	18
2005-10-01	18.4
2006-01-01	18.7
2006-04-01	16
2006-07-01	17.3
2006-10-01	14.5
2007-01-01	12.2
2007-04-01	10.7
2007-07-01	10.1
2007-10-01	9.4
2008-01-01	10.4
2008-04-01	9.2
2008-07-01	9.6
2008-10-01	10
2009-01-01	12.7
2009-04-01	15
2009-07-01	18.7
2009-10-01	19.8
2010-01-01	20.3
2010-04-01	18
2010-07-01	17.6
2010-10-01	17.1
2011-01-01	17.2
2011-04-01	17.4
2011-07-01	18.9
2011-10-01	19
2012-01-01	20.2
2012-04-01	19.7
2012-07-01	19.6
2012-10-01	19.9
2013-01-01	20
2013-04-01	16.6
2013-07-01	18.9
2013-10-01	19
2014-01-01	16
2014-04-01	13.9
2014-07-01	15.2
2014-10-01	15.1
2015-01-01	14.2
2015-04-01	10.7
2015-07-01	10.7
2015-10-01	9.5
2016-01-01	8.9
2016-04-01	10.1
2016-07-01	10.3
2016-10-01	10.3
2017-01-01	7.5
2017-04-01	7.0
2017-07-01	8.6
2017-10-01	6.3
2018-01-01	6.4
2018-04-01	5.9