Quarter	Percent
1999-04-01	71.1
2000-01-01	70
2000-04-01	71.2
2000-07-01	71.2
2000-10-01	70.6
2001-01-01	70.2
2001-04-01	71.1
2001-07-01	71
2001-10-01	70.8
2002-01-01	70.3
2002-04-01	71.1
2002-07-01	71
2002-10-01	70
2003-01-01	69.3
2003-04-01	69.7
2003-07-01	69.9
2003-10-01	69.3
2004-01-01	68.6
2004-04-01	69.5
2004-07-01	69.7
2004-10-01	69.2
2005-01-01	68.4
2005-04-01	69
2005-07-01	69.5
2005-10-01	69.3
2006-01-01	68.6
2006-04-01	69.3
2006-07-01	69.9
2006-10-01	69.9
2007-01-01	69.8
2007-04-01	70.7
2007-07-01	71.2
2007-10-01	71.5
2008-01-01	71.6
2008-04-01	72.3
2008-07-01	72.3
2008-10-01	71.4
2009-01-01	70.7
2009-04-01	71
2009-07-01	70.2
2009-10-01	69.7
2010-01-01	69.1
2010-04-01	69.6
2010-07-01	69.3
2010-10-01	69
2011-01-01	68.6
2011-04-01	69
2011-07-01	69.4
2011-10-01	69.1
2012-01-01	69
2012-04-01	69.7
2012-07-01	69.4
2012-10-01	68.7
2013-01-01	68.3
2013-04-01	68.8
2013-07-01	69
2013-10-01	68.5
2014-01-01	62.2
2014-04-01	62.9
2014-07-01	62.7
2014-10-01	62.6
2015-01-01	61.9
2015-04-01	62.6
2015-07-01	62.4
2015-10-01	61.8
2016-01-01	61.6
2016-04-01	61.6
2016-07-01	61.9
2016-10-01	61.0
2017-01-01	60.8
2017-04-01	61.3
2017-07-01	61.3
2017-10-01	60.9
2018-01-01	61.1
2018-04-01	61.7