Quarter	Percent
1999-04-01	21.7
2000-04-01	20.2
2001-04-01	21.5
2002-04-01	21.7
2003-01-01	24.3
2003-04-01	21.3
2003-07-01	20.4
2003-10-01	24.8
2004-01-01	24.8
2004-04-01	23.2
2004-07-01	23.7
2004-10-01	25.5
2005-01-01	23.7
2005-04-01	21.7
2005-07-01	23.3
2005-10-01	22.9
2006-01-01	22.9
2006-04-01	20.6
2006-07-01	21.7
2006-10-01	23.8
2007-01-01	22.8
2007-04-01	20.2
2007-07-01	21.7
2007-10-01	24.3
2008-01-01	24.5
2008-04-01	22
2008-07-01	22.3
2008-10-01	23.3
2009-01-01	25.3
2009-04-01	23.4
2009-07-01	22.7
2009-10-01	23
2010-01-01	24.3
2010-04-01	21.6
2010-07-01	22.8
2010-10-01	24.1
2011-01-01	24.6
2011-04-01	20.3
2011-07-01	23.2
2011-10-01	26.3
2012-01-01	24.8
2012-04-01	20.2
2012-07-01	22.6
2012-10-01	24
2013-01-01	24.4
2013-04-01	21.1
2013-07-01	21.3
2013-10-01	22.6
2014-01-01	23.7
2014-04-01	19.9
2014-07-01	20.4
2014-10-01	21.4
2015-01-01	21.7
2015-04-01	18.5
2015-07-01	20.4
2015-10-01	20.8
2016-01-01	22.1
2016-04-01	18.9
2016-07-01	19.3
2016-10-01	20.6
2017-01-01	20.9
2017-04-01	20.1
2017-07-01	21.9
2017-10-01	21.6
2018-01-01	22.8
2018-04-01	21.5