Quarter	Percent
2005-01-01	89.9
2005-04-01	90.6
2005-07-01	90.3
2005-10-01	88.9
2006-01-01	88.9
2006-04-01	88.6
2006-07-01	88.2
2006-10-01	88.0
2007-01-01	87.2
2007-04-01	87.6
2007-07-01	88.4
2007-10-01	87.4
2008-01-01	86.5
2008-04-01	87.2
2008-07-01	87.6
2008-10-01	88.0
2009-01-01	86.5
2009-04-01	87.7
2009-07-01	89.1
2009-10-01	88.8
2010-01-01	87.5
2010-04-01	88.4
2010-07-01	89.8
2010-10-01	90.2
2011-01-01	90.8
2011-04-01	91.5
2011-07-01	90.3
2011-10-01	90.1
2012-01-01	90.0
2012-04-01	91.0
2012-07-01	90.8
2012-10-01	90.2
2013-01-01	90.1
2013-04-01	91.1
2013-07-01	90.7
2013-10-01	90.7
2014-01-01	91.0
2014-04-01	90.8
2014-07-01	90.8
2014-10-01	90.7
2015-01-01	90.4
2015-04-01	90.1
2015-07-01	90.4
2015-10-01	90.6
2016-01-01	90.2
2016-04-01	90.4
2016-07-01	90.2
2016-10-01	90.2
2017-01-01	90.4
2017-04-01	90.3
2017-07-01	90.6
2017-10-01	90.4
2018-01-01	90.3
2018-04-01	91.5