Quarter	Percent
1998-04-01	3.1
1999-04-01	2.5
2000-04-01	2.7
2001-04-01	1.7
2002-04-01	2.0
2003-04-01	2.5
2004-04-01	3.2
2005-04-01	3.7
2006-04-01	3.1
2007-04-01	3.1
2008-04-01	2.6
2009-04-01	2.7
2010-01-01	3.9
2010-04-01	3.4
2010-07-01	3.5
2010-10-01	3.2
2011-01-01	3.8
2011-04-01	3.6
2011-07-01	3.1
2011-10-01	3.6
2012-01-01	3.7
2012-04-01	3.2
2012-07-01	2.9
2012-10-01	3.6
2013-01-01	3.4
2013-04-01	3.6
2013-07-01	2.9
2013-10-01	3.1
2014-01-01	3.2
2014-04-01	3.6
2014-07-01	3.0
2014-10-01	3.5
2015-01-01	3.9
2015-04-01	3.5
2015-07-01	4.5
2015-10-01	4.3
2016-01-01	3.8
2016-04-01	4.1
2016-07-01	3.6
2016-10-01	3.7
2017-01-01	3.9
2017-04-01	3.7
2017-07-01	3.6
2017-10-01	4.1
2018-01-01	4.3
2018-04-01	4.1