Quarter	Percent
1999-04-01	43
2000-01-01	42.3
2000-04-01	43.2
2000-07-01	46.4
2000-10-01	47
2001-01-01	45.3
2001-04-01	38.8
2001-07-01	43.8
2001-10-01	47
2002-01-01	41.4
2002-04-01	37.4
2002-07-01	42.8
2002-10-01	44.3
2003-01-01	39.2
2003-04-01	48.5
2003-07-01	51.7
2003-10-01	41.3
2004-01-01	42.2
2004-04-01	47
2004-07-01	50.4
2004-10-01	41.2
2005-01-01	37.7
2005-04-01	41.3
2005-07-01	42.4
2005-10-01	43.2
2006-01-01	40.6
2006-04-01	40.1
2006-07-01	41
2006-10-01	41.7
2007-01-01	42.5
2007-04-01	44.2
2007-07-01	46.2
2007-10-01	41.2
2008-01-01	41.9
2008-04-01	42.1
2008-07-01	47.4
2008-10-01	46.6
2009-01-01	43.5
2009-04-01	44.1
2009-07-01	48.3
2009-10-01	39.3
2010-01-01	43.6
2010-04-01	40.4
2010-07-01	41.6
2010-10-01	39
2011-01-01	41.6
2011-04-01	43.3
2011-07-01	47.6
2011-10-01	41.2
2012-01-01	42.2
2012-04-01	44.5
2012-07-01	47.3
2012-10-01	43.1
2013-01-01	41.4
2013-04-01	40.4
2013-07-01	43.5
2013-10-01	40.2
2014-01-01	40.4
2014-04-01	42.2
2014-07-01	42.6
2014-10-01	40.3
2015-01-01	41.5
2015-04-01	51.2
2015-07-01	50.5
2015-10-01	39.5
2016-01-01	43.5
2016-04-01	45.4
2016-07-01	51.0
2016-10-01	44.5
2017-01-01	47.4
2017-04-01	49.9
2017-07-01	51.4
2017-10-01	50.1
2018-01-01	50.8
2018-04-01	51.5