Quarter	Percent
1999-01-01	68.5
1999-04-01	68.6
1999-07-01	68.9
1999-10-01	68.1
2000-01-01	67.1
2000-04-01	68.2
2000-07-01	69
2000-10-01	68.9
2001-01-01	67.9
2001-04-01	68.3
2001-07-01	69.1
2001-10-01	68.9
2002-01-01	67.3
2002-04-01	68.2
2002-07-01	68.9
2002-10-01	68
2003-01-01	68
2003-04-01	67.8
2003-07-01	68.4
2003-10-01	67.5
2004-01-01	67.3
2004-04-01	68.1
2004-07-01	68.7
2004-10-01	67.8
2005-01-01	67.3
2005-04-01	68.3
2005-07-01	68.1
2005-10-01	68
2006-01-01	67.8
2006-04-01	68.4
2006-07-01	69.4
2006-10-01	69.3
2007-01-01	68.7
2007-04-01	68.8
2007-07-01	68.5
2007-10-01	68.1
2008-01-01	67.9
2008-04-01	69.4
2008-07-01	69.9
2008-10-01	68.6
2009-01-01	66.4
2009-04-01	65.8
2009-07-01	66
2009-10-01	64
2010-01-01	62.9
2010-04-01	63.1
2010-07-01	63.6
2010-10-01	63.6
2011-01-01	62.7
2011-04-01	63.2
2011-07-01	63.7
2011-10-01	63
2012-01-01	62.1
2012-04-01	62.4
2012-07-01	62.3
2012-10-01	62.5
2013-01-01	61.6
2013-04-01	62
2013-07-01	61.8
2013-10-01	61.7
2014-01-01	61.1
2014-04-01	62.1
2014-07-01	62.9
2014-10-01	62.6
2015-01-01	62.1
2015-04-01	62.8
2015-07-01	63.0
2015-10-01	63.3
2016-01-01	63.2
2016-04-01	64.1
2016-07-01	64.4
2016-10-01	63.8
2017-01-01	61.8
2017-04-01	62.8
2017-07-01	63.1
2017-10-01	63.1
2018-01-01	62.6
2018-04-01	63.7