Quarter	Percent
1999-04-01	49.4
1999-07-01	49.5
1999-10-01	49.7
2000-01-01	49.9
2000-04-01	50.4
2000-07-01	51.2
2000-10-01	51.4
2001-01-01	51.7
2001-04-01	52.2
2001-07-01	52.4
2001-10-01	52.7
2002-01-01	52.9
2002-04-01	53.2
2002-07-01	53.5
2002-10-01	54.1
2003-01-01	54.2
2003-04-01	55.4
2003-07-01	56
2003-10-01	55.8
2004-01-01	55.9
2004-04-01	56.1
2004-07-01	56.0
2004-10-01	56.6
2005-01-01	56.8
2005-04-01	56.8
2005-07-01	56.7
2005-10-01	57
2006-01-01	56.8
2006-04-01	57.3
2006-07-01	57.6
2006-10-01	57.5
2007-01-01	57
2007-04-01	57.3
2007-07-01	57.2
2007-10-01	58
2008-01-01	57.9
2008-04-01	58.1
2008-07-01	57.8
2008-10-01	58
2009-01-01	57.9
2009-04-01	57.6
2009-07-01	57.4
2009-10-01	57.2
2010-01-01	57.6
2010-04-01	56.9
2010-07-01	57.3
2010-10-01	56.8
2011-01-01	56.9
2011-04-01	56.7
2011-07-01	56.5
2011-10-01	56.6
2012-01-01	57.2
2012-04-01	58
2012-07-01	58.3
2012-10-01	58.8
2013-01-01	58.7
2013-04-01	59.6
2013-07-01	60.2
2013-10-01	60.6
2014-01-01	60.8
2014-04-01	60.8
2014-07-01	60.9
2014-10-01	61.3
2015-01-01	61.6
2015-04-01	61.8
2015-07-01	62.3
2015-10-01	63.1
2016-01-01	62.9
2016-04-01	63.6
2016-07-01	63.4
2016-10-01	63.6
2017-01-01	63.9
2017-04-01	64.0
2017-07-01	63.9
2017-10-01	64.4
2018-01-01	65.0
2018-04-01	65.3