Quarter	Percent
1998-04-01	84.9
1999-04-01	85.2
2000-04-01	85.4
2001-04-01	86.1
2002-04-01	86
2003-04-01	84.8
2004-04-01	84.7
2005-04-01	85.1
2006-04-01	85.2
2007-04-01	86.1
2008-04-01	87.2
2009-04-01	86.7
2010-01-01	83.6
2010-04-01	84.5
2010-07-01	84.6
2010-10-01	84.6
2011-01-01	85.1
2011-04-01	85.8
2011-07-01	85.2
2011-10-01	85.6
2012-01-01	85.5
2012-04-01	85.9
2012-07-01	85.9
2012-10-01	85.7
2013-01-01	84.7
2013-04-01	85.2
2013-07-01	85.3
2013-10-01	85.7
2014-01-01	84.9
2014-04-01	85.8
2014-07-01	85.8
2014-10-01	86.6
2015-01-01	86.2
2015-04-01	86.3
2015-07-01	85.9
2015-10-01	86.7
2016-01-01	86.3
2016-04-01	86.3
2016-07-01	86.1
2016-10-01	86.5
2017-01-01	85.8
2017-04-01	86.4
2017-07-01	86.1
2017-10-01	86.4
2018-01-01	86.2
2018-04-01	86.5