Quarter	Percent
1998-01-01	75.5
1999-01-01	76.3
1999-04-01	75.5
1999-07-01	75
1999-10-01	74.9
2000-01-01	76.8
2000-04-01	76.2
2000-07-01	76.5
2000-10-01	76.6
2001-01-01	76.9
2001-04-01	77.2
2001-07-01	77.1
2001-10-01	77.4
2002-01-01	79.1
2002-04-01	79
2002-07-01	79
2002-10-01	79.1
2003-01-01	79.7
2003-04-01	80.1
2003-07-01	80.4
2003-10-01	79.6
2004-01-01	78.6
2004-04-01	78.7
2004-07-01	79.4
2004-10-01	78.7
2005-01-01	79.2
2005-04-01	79.3
2005-07-01	79.9
2005-10-01	79.2
2006-01-01	79.7
2006-04-01	80.2
2006-07-01	80.6
2006-10-01	79.8
2007-01-01	80
2007-04-01	80.4
2007-07-01	81.3
2007-10-01	80.3
2008-01-01	80.5
2008-04-01	81.1
2008-07-01	81
2008-10-01	81.1
2009-01-01	81.8
2009-04-01	82.2
2009-07-01	82.5
2009-10-01	81.7
2010-01-01	82
2010-04-01	82.2
2010-07-01	82.3
2010-10-01	82.9
2011-01-01	82.8
2011-04-01	82.9
2011-07-01	83.2
2011-10-01	84
2012-01-01	84
2012-04-01	84.1
2012-07-01	84.3
2012-10-01	83.6
2013-01-01	84.5
2013-04-01	84.4
2013-07-01	84.9
2013-10-01	84.3
2014-01-01	85
2014-04-01	84.8
2014-07-01	84.4
2014-10-01	84
2015-01-01	84.1
2015-04-01	84.2
2015-07-01	84.4
2015-10-01	84.8
2016-01-01	84.7
2016-04-01	84.9
2016-07-01	85.1
2016-10-01	84.9
2017-01-01	84.9
2017-04-01	85.0
2017-07-01	85.0
2017-10-01	85.3
2018-01-01	84.8
2018-04-01	84.8