Quarter	Percent
2000-04-01	44.5
2001-04-01	44.9
2002-04-01	46.5
2003-04-01	47.7
2004-04-01	48.4
2005-01-01	49.3
2005-04-01	49.7
2005-07-01	50.2
2005-10-01	50.4
2006-01-01	49.9
2006-04-01	50.9
2006-07-01	51.2
2006-10-01	51.2
2007-01-01	51.3
2007-04-01	52.4
2007-07-01	52.8
2007-10-01	52.6
2008-01-01	52.3
2008-04-01	53.3
2008-07-01	53.6
2008-10-01	53.7
2009-01-01	53
2009-04-01	53.9
2009-07-01	53.3
2009-10-01	53.6
2010-01-01	53.2
2010-04-01	53.7
2010-07-01	53.8
2010-10-01	54.0
2011-01-01	53.6
2011-04-01	54.4
2011-07-01	54.4
2011-10-01	55.0
2012-01-01	54.5
2012-04-01	55.5
2012-07-01	56.1
2012-10-01	56.3
2013-01-01	55.5
2013-04-01	56.5
2013-07-01	57.3
2013-10-01	57.4
2014-01-01	57.1
2014-04-01	57.8
2014-07-01	58.4
2014-10-01	58.6
2015-01-01	58.5
2015-04-01	59.3
2015-07-01	60.1
2015-10-01	60.1
2016-01-01	60.7
2016-04-01	61.5
2016-07-01	62.0
2016-10-01	62.0
2017-01-01	61.7
2017-04-01	63.2
2017-07-01	63.7
2017-10-01	64.3
2018-01-01	63.8
2018-04-01	64.7