Quarter	Percent
1998-04-01	38.3
1999-04-01	41.4
2000-04-01	40.4
2001-01-01	45.8
2001-04-01	52.5
2001-07-01	54.5
2001-10-01	47.5
2002-01-01	47.1
2002-04-01	50.6
2002-07-01	54.2
2002-10-01	46.9
2003-01-01	46.3
2003-04-01	50.7
2003-07-01	51.6
2003-10-01	44.4
2004-01-01	43.8
2004-04-01	48.2
2004-07-01	52.4
2004-10-01	44.7
2005-01-01	43
2005-04-01	57.1
2005-07-01	54.8
2005-10-01	48.3
2006-01-01	46.6
2006-04-01	56
2006-07-01	57.2
2006-10-01	47.7
2007-01-01	47.4
2007-04-01	56.6
2007-07-01	57
2007-10-01	49.9
2008-01-01	49.7
2008-04-01	58.2
2008-07-01	56.5
2008-10-01	47.9
2009-01-01	48.3
2009-04-01	57.3
2009-07-01	52.1
2009-10-01	46.2
2010-01-01	48
2010-04-01	55.8
2010-07-01	54.6
2010-10-01	46.9
2011-01-01	49.4
2011-04-01	57.1
2011-07-01	55.7
2011-10-01	49
2012-01-01	50.1
2012-04-01	58
2012-07-01	56.7
2012-10-01	49
2013-01-01	51.1
2013-04-01	59.2
2013-07-01	58.2
2013-10-01	52.1
2014-01-01	52.5
2014-04-01	59.6
2014-07-01	60.7
2014-10-01	51.4
2015-01-01	53.9
2015-04-01	60.6
2015-07-01	59.8
2015-10-01	51.8
2016-01-01	54.0
2016-04-01	60.7
2016-07-01	56.7
2016-10-01	50.8
2017-01-01	53.0
2017-04-01	58.7
2017-07-01	58.1
2017-10-01	51.7
2018-01-01	51.8
2018-04-01	59.3