Quarter	Percent
2000-04-01	44.8
2001-04-01	45.7
2002-04-01	46.4
2003-04-01	47.1
2004-04-01	47.5
2005-01-01	48.1
2005-04-01	48.5
2005-07-01	48.6
2005-10-01	48.7
2006-01-01	48.9
2006-04-01	49.5
2006-07-01	49.7
2006-10-01	49.9
2007-01-01	49.8
2007-04-01	50.5
2007-07-01	50.9
2007-10-01	51.0
2008-01-01	50.9
2008-04-01	51.2
2008-07-01	51.5
2008-10-01	51.4
2009-01-01	50.7
2009-04-01	50.9
2009-07-01	50.8
2009-10-01	50.9
2010-01-01	50.4
2010-04-01	50.8
2010-07-01	50.8
2010-10-01	50.9
2011-01-01	50.6
2011-04-01	51.3
2011-07-01	51.1
2011-10-01	51.1
2012-01-01	50.7
2012-04-01	51.1
2012-07-01	51.1
2012-10-01	50.9
2013-01-01	50.5
2013-04-01	50.9
2013-07-01	51.1
2013-10-01	50.9
2014-01-01	50.8
2014-04-01	51.3
2014-07-01	51.4
2014-10-01	51.4
2015-01-01	51.2
2015-04-01	51.8
2015-07-01	52.0
2015-10-01	52.0
2016-01-01	52.0
2016-04-01	52.5
2016-07-01	52.9
2016-10-01	52.9
2017-01-01	52.6
2017-04-01	53.3
2017-07-01	53.5
2017-10-01	53.7
2018-01-01	53.3
2018-04-01	54.0