Quarter	Percent
1999-04-01	2.1
2000-04-01	1.9
2001-04-01	1.9
2002-04-01	3.0
2003-01-01	3.9
2003-04-01	4.1
2003-07-01	2.7
2003-10-01	3.0
2004-01-01	3.1
2004-04-01	4.1
2004-07-01	2.5
2004-10-01	2.4
2005-01-01	3.1
2005-04-01	3.0
2005-07-01	1.7
2005-10-01	2.7
2006-01-01	2.4
2006-04-01	4.1
2006-07-01	2.5
2006-10-01	2.4
2007-01-01	1.9
2007-04-01	3.2
2007-07-01	2.0
2007-10-01	1.9
2008-01-01	2.2
2008-04-01	3.1
2008-07-01	2.6
2008-10-01	4.1
2009-01-01	7.3
2009-04-01	9.4
2009-07-01	6.1
2009-10-01	6.8
2010-01-01	7.7
2010-04-01	9.0
2010-07-01	6.7
2010-10-01	7.6
2011-01-01	7.9
2011-04-01	8.6
2011-07-01	5.9
2011-10-01	6.1
2012-01-01	7.1
2012-04-01	7.4
2012-07-01	5.0
2012-10-01	4.9
2013-01-01	5.9
2013-04-01	7.0
2013-07-01	4.5
2013-10-01	4.6
2014-01-01	5.9
2014-04-01	5.9
2014-07-01	4.1
2014-10-01	4.3
2015-01-01	4.4
2015-04-01	5.3
2015-07-01	3.6
2015-10-01	3.3
2016-01-01	3.4
2016-04-01	3.8
2016-07-01	2.6
2016-10-01	2.7
2017-01-01	3.0
2017-04-01	3.6
2017-07-01	2.3
2017-10-01	2.7
2018-01-01	3.0
2018-04-01	3.5