Quarter	Percent
2005-01-01	62.8
2005-04-01	63.3
2005-07-01	63.0
2005-10-01	62.5
2006-01-01	61.8
2006-04-01	61.2
2006-07-01	61.5
2006-10-01	60.7
2007-01-01	60.9
2007-04-01	62.1
2007-07-01	63.0
2007-10-01	61.9
2008-01-01	61.3
2008-04-01	62.5
2008-07-01	62.6
2008-10-01	62.3
2009-01-01	61.6
2009-04-01	62.3
2009-07-01	62.5
2009-10-01	61.6
2010-01-01	61.0
2010-04-01	61.6
2010-07-01	62.4
2010-10-01	63.0
2011-01-01	63.1
2011-04-01	63.7
2011-07-01	62.9
2011-10-01	62.5
2012-01-01	62.2
2012-04-01	63.5
2012-07-01	64.1
2012-10-01	63.2
2013-01-01	63.3
2013-04-01	64.1
2013-07-01	64.5
2013-10-01	64.6
2014-01-01	65.0
2014-04-01	64.9
2014-07-01	65.5
2014-10-01	64.8
2015-01-01	64.6
2015-04-01	65.1
2015-07-01	64.8
2015-10-01	65.0
2016-01-01	65.0
2016-04-01	66.6
2016-07-01	66.4
2016-10-01	66.0
2017-01-01	66.3
2017-04-01	66.4
2017-07-01	66.4
2017-10-01	66.5
2018-01-01	67.0
2018-04-01	67.7