Quarter	Percent
1999-04-01	29.5
2000-04-01	28.3
2001-04-01	30.3
2002-04-01	28.4
2003-01-01	26.1
2003-04-01	26.1
2003-07-01	26.1
2003-10-01	26.1
2004-01-01	20.5
2004-04-01	20.5
2004-07-01	20.5
2004-10-01	20.5
2005-01-01	21.3
2005-04-01	21.3
2005-07-01	21.3
2005-10-01	21.3
2006-01-01	21.2
2006-04-01	21.2
2006-07-01	21.2
2006-10-01	21.2
2007-01-01	17.4
2007-04-01	15.2
2007-07-01	19.9
2007-10-01	21.2
2008-01-01	17.3
2008-04-01	22.2
2008-07-01	20.6
2008-10-01	22.1
2009-01-01	21.1
2009-04-01	25.5
2009-07-01	24.1
2009-10-01	26
2010-01-01	17.4
2010-04-01	19.3
2010-07-01	23.8
2010-10-01	20.9
2011-01-01	19.3
2011-04-01	15.1
2011-07-01	20.4
2011-10-01	19.2
2012-01-01	19.1
2012-04-01	17.2
2012-07-01	22
2012-10-01	21.9
2013-01-01	19.8
2013-04-01	19.6
2013-07-01	15
2013-10-01	23.2
2014-01-01	24.9
2014-04-01	16.2
2014-07-01	15.9
2014-10-01	18.2
2015-01-01	29.0
2015-04-01	28.5
2015-07-01	32.0
2015-10-01	25.6
2016-01-01	21.0
2016-04-01	25.4
2016-07-01	31.4
2016-10-01	23.9
2017-01-01	27.3
2017-04-01	20.4
2017-07-01	26.4
2017-10-01	23.9
2018-01-01	26.6
2018-04-01	24.9