Quarter	Percent
1999-04-01	82.3
2000-04-01	83.2
2001-04-01	85.6
2002-04-01	81.9
2003-01-01	78.8
2003-04-01	78.8
2003-07-01	78.8
2003-10-01	78.8
2004-01-01	77.4
2004-04-01	77.4
2004-07-01	77.4
2004-10-01	77.4
2005-01-01	74.9
2005-04-01	74.9
2005-07-01	74.9
2005-10-01	74.9
2006-01-01	71.5
2006-04-01	71.5
2006-07-01	71.5
2006-10-01	71.5
2007-01-01	71.6
2007-04-01	72.6
2007-07-01	67.7
2007-10-01	71.6
2008-01-01	67.8
2008-04-01	67.5
2008-07-01	69.2
2008-10-01	74.4
2009-01-01	72.1
2009-04-01	68
2009-07-01	69.6
2009-10-01	67.9
2010-01-01	70
2010-04-01	65.4
2010-07-01	70.2
2010-10-01	66.5
2011-01-01	67.5
2011-04-01	67.5
2011-07-01	64.8
2011-10-01	71.8
2012-01-01	65.4
2012-04-01	64.1
2012-07-01	61.8
2012-10-01	67.8
2013-01-01	69.8
2013-04-01	58.5
2013-07-01	66.3
2013-10-01	68.6
2014-01-01	61.4
2014-04-01	64.7
2014-07-01	62.9
2014-10-01	64.9
2015-01-01	61.5
2015-04-01	65.1
2015-07-01	69.0
2015-10-01	64.3
2016-01-01	63.9
2016-04-01	67.7
2016-07-01	67.8
2016-10-01	65.1
2017-01-01	66.2
2017-04-01	66.2
2017-07-01	64.0
2017-10-01	63.2
2018-01-01	64.5
2018-04-01	64.0