Quarter	Percent
1998-04-01	94.3
1999-04-01	95.1
2000-04-01	95.2
2001-04-01	95.3
2002-04-01	93.9
2003-04-01	92.4
2004-04-01	92.3
2005-04-01	92.6
2006-04-01	92.9
2007-04-01	93.6
2008-04-01	93.7
2009-04-01	92.8
2010-01-01	89.6
2010-04-01	90.9
2010-07-01	91.3
2010-10-01	90.8
2011-01-01	91.1
2011-04-01	92.0
2011-07-01	92.0
2011-10-01	91.2
2012-01-01	91.1
2012-04-01	91.9
2012-07-01	91.8
2012-10-01	91.2
2013-01-01	90.0
2013-04-01	90.5
2013-07-01	90.8
2013-10-01	91.3
2014-01-01	89.9
2014-04-01	90.9
2014-07-01	90.9
2014-10-01	91.5
2015-01-01	91.1
2015-04-01	91.5
2015-07-01	91.4
2015-10-01	92.2
2016-01-01	90.8
2016-04-01	91.5
2016-07-01	91.3
2016-10-01	91.3
2017-01-01	90.2
2017-04-01	91.7
2017-07-01	91.3
2017-10-01	91.2
2018-01-01	90.8
2018-04-01	91.7