Quarter	Percent
1998-04-01	90.2
1999-04-01	89.7
2000-04-01	89.4
2001-04-01	89.2
2002-04-01	88.7
2003-04-01	88.5
2004-04-01	88
2005-04-01	87.4
2006-04-01	87.8
2007-04-01	88.2
2008-04-01	88
2009-04-01	87.8
2010-01-01	86.8
2010-04-01	87.2
2010-07-01	87.8
2010-10-01	87.1
2011-01-01	87.5
2011-04-01	87.5
2011-07-01	88.1
2011-10-01	87.9
2012-01-01	87.2
2012-04-01	87.2
2012-07-01	88.5
2012-10-01	88.1
2013-01-01	87.6
2013-04-01	87.2
2013-07-01	87.8
2013-10-01	87.9
2014-01-01	87.3
2014-04-01	87.3
2014-07-01	87.9
2014-10-01	87.9
2015-01-01	87.8
2015-04-01	87.4
2015-07-01	87.8
2015-10-01	88.4
2016-01-01	88.0
2016-04-01	87.7
2016-07-01	88.4
2016-10-01	88.6
2017-01-01	88.0
2017-04-01	88.3
2017-07-01	89.0
2017-10-01	88.6
2018-01-01	88.1
2018-04-01	88.5