Quarter	Percent
2000-04-01	60.1
2001-04-01	60.2
2002-04-01	60.5
2003-04-01	61.1
2004-04-01	61.5
2005-01-01	61.8
2005-04-01	62.2
2005-07-01	62.3
2005-10-01	62.5
2006-01-01	62.5
2006-04-01	62.8
2006-07-01	63.2
2006-10-01	63
2007-01-01	62.7
2007-04-01	63.0
2007-07-01	63.5
2007-10-01	63.4
2008-01-01	63.2
2008-04-01	63.6
2008-07-01	64.0
2008-10-01	63.9
2009-01-01	63.8
2009-04-01	64.1
2009-07-01	64.2
2009-10-01	64.2
2010-01-01	64.1
2010-04-01	64.4
2010-07-01	64.6
2010-10-01	64.5
2011-01-01	64.4
2011-04-01	64.7
2011-07-01	64.9
2011-10-01	65.1
2012-01-01	65.1
2012-04-01	65.5
2012-07-01	65.8
2012-10-01	65.9
2013-01-01	65.7
2013-04-01	66.0
2013-07-01	66.2
2013-10-01	66.3
2014-01-01	66.2
2014-04-01	66.4
2014-07-01	66.7
2014-10-01	66.8
2015-01-01	66.5
2015-04-01	66.8
2015-07-01	66.9
2015-10-01	67.0
2016-01-01	66.9
2016-04-01	67.3
2016-07-01	67.6
2016-10-01	67.5
2017-01-01	67.4
2017-04-01	67.8
2017-07-01	68.0
2017-10-01	68.0
2018-01-01	67.9
2018-04-01	68.2