Quarter	Percent
1998-04-01	29.6
1998-10-01	29.6
1999-04-01	30.3
1999-10-01	30.5
2000-04-01	32.7
2000-10-01	33.7
2001-04-01	33.2
2001-10-01	32.8
2002-01-01	33.4
2002-04-01	31.3
2002-07-01	30.5
2002-10-01	31.5
2003-01-01	32.0
2003-04-01	32.5
2003-07-01	30.3
2003-10-01	33.1
2004-01-01	32.3
2004-04-01	31.5
2004-07-01	31.2
2004-10-01	32.1
2005-01-01	31.6
2005-04-01	31.8
2005-07-01	30.4
2005-10-01	31.8
2006-01-01	29.7
2006-04-01	30.8
2006-07-01	26.9
2006-10-01	29.3
2007-01-01	29.1
2007-04-01	28.1
2007-07-01	25.7
2007-10-01	26.9
2008-01-01	27.0
2008-04-01	26.8
2008-07-01	26.5
2008-10-01	26.8
2009-01-01	27.7
2009-04-01	28.3
2009-07-01	29.8
2009-10-01	31.6
2010-01-01	31.0
2010-04-01	31.5
2010-07-01	31.0
2010-10-01	31.8
2011-01-01	31.5
2011-04-01	30.5
2011-07-01	31.1
2011-10-01	30.3
2012-01-01	30.8
2012-04-01	29.3
2012-07-01	29.1
2012-10-01	28.5
2013-01-01	29.6
2013-04-01	31.2
2013-07-01	28.8
2013-10-01	28.7
2014-01-01	29.0
2014-04-01	29.2
2014-07-01	28.7
2014-10-01	28.3
2015-01-01	28.6
2015-04-01	27.6
2015-07-01	27.5
2015-10-01	26.8
2016-01-01	28.0
2016-04-01	27.7
2016-07-01	27.1
2016-10-01	28.3
2017-01-01	27.7
2017-04-01	27.2
2017-07-01	26.3
2017-10-01	26.2
2018-01-01	26.8
2018-04-01	26.2