Quarter	Percent
1999-01-01	14.9
1999-04-01	13.7
1999-07-01	13.5
1999-10-01	13.4
2000-01-01	13.1
2000-04-01	12.3
2000-07-01	12
2000-10-01	11.9
2001-01-01	9.7
2001-04-01	9.1
2001-07-01	8.9
2001-10-01	9.3
2002-01-01	10.3
2002-04-01	10
2002-07-01	10.2
2002-10-01	10.3
2003-01-01	10.8
2003-04-01	10.1
2003-07-01	10
2003-10-01	10.2
2004-01-01	10.4
2004-04-01	9.9
2004-07-01	9.5
2004-10-01	9.4
2005-01-01	8.9
2005-04-01	8.0
2005-07-01	7.3
2005-10-01	7.7
2006-01-01	8.1
2006-04-01	7.4
2006-07-01	7.1
2006-10-01	7.3
2007-01-01	7.5
2007-04-01	6.8
2007-07-01	6.9
2007-10-01	7.6
2008-01-01	8.5
2008-04-01	9.1
2008-07-01	10
2008-10-01	12.6
2009-01-01	15.9
2009-04-01	16.2
2009-07-01	16
2009-10-01	17.3
2010-01-01	18.5
2010-04-01	18.3
2010-07-01	18.1
2010-10-01	18.6
2011-01-01	19.6
2011-04-01	19.1
2011-07-01	19.7
2011-10-01	21.1
2012-01-01	22.7
2012-04-01	22.8
2012-07-01	23.2
2012-10-01	24.3
2013-01-01	25.3
2013-04-01	24.4
2013-07-01	24
2013-10-01	24.2
2014-01-01	24.4
2014-04-01	22.8
2014-07-01	21.9
2014-10-01	22.1
2015-01-01	22.4
2015-04-01	20.9
2015-07-01	19.5
2015-10-01	19.4
2016-01-01	19.7
2016-04-01	18.5
2016-07-01	17.5
2016-10-01	17.2
2017-01-01	17.6
2017-04-01	15.8
2017-07-01	15.0
2017-10-01	15.2
2018-01-01	15.6
2018-04-01	14.0
2018-07-01	13.4