Quarter	Percent
1998-04-01	42.9
1999-04-01	43.1
2000-04-01	41.1
2001-01-01	47.2
2001-04-01	52.2
2001-07-01	54.5
2001-10-01	46.2
2002-01-01	44.9
2002-04-01	50.5
2002-07-01	52.7
2002-10-01	45.8
2003-01-01	43.2
2003-04-01	50.5
2003-07-01	51.7
2003-10-01	43.6
2004-01-01	43
2004-04-01	48.9
2004-07-01	51.6
2004-10-01	44.8
2005-01-01	43.7
2005-04-01	54.5
2005-07-01	52.8
2005-10-01	44.9
2006-01-01	45
2006-04-01	55.3
2006-07-01	54.7
2006-10-01	48.2
2007-01-01	49.1
2007-04-01	53.6
2007-07-01	55.9
2007-10-01	48.5
2008-01-01	48.5
2008-04-01	57.3
2008-07-01	56.4
2008-10-01	48.3
2009-01-01	47.2
2009-04-01	56.5
2009-07-01	54
2009-10-01	46.6
2010-01-01	46.3
2010-04-01	56.7
2010-07-01	55.8
2010-10-01	49
2011-01-01	49.1
2011-04-01	57.9
2011-07-01	56.6
2011-10-01	49
2012-01-01	47.2
2012-04-01	55.7
2012-07-01	55.4
2012-10-01	48.7
2013-01-01	49.7
2013-04-01	57.8
2013-07-01	57.4
2013-10-01	50.6
2014-01-01	51.1
2014-04-01	59.1
2014-07-01	58.1
2014-10-01	51.2
2015-01-01	51.0
2015-04-01	57.2
2015-07-01	56.9
2015-10-01	50.3
2016-01-01	51.6
2016-04-01	59.4
2016-07-01	55.7
2016-10-01	50.1
2017-01-01	50.9
2017-04-01	58.0
2017-07-01	57.3
2017-10-01	50.1
2018-01-01	50.3
2018-04-01	56.6