Quarter	Percent
1998-04-01	61.7
1999-04-01	58.6
2000-04-01	59.6
2001-01-01	54.2
2001-04-01	47.5
2001-07-01	45.5
2001-10-01	52.5
2002-01-01	52.9
2002-04-01	49.4
2002-07-01	45.8
2002-10-01	53.1
2003-01-01	53.7
2003-04-01	49.3
2003-07-01	48.4
2003-10-01	55.6
2004-01-01	56.2
2004-04-01	51.8
2004-07-01	47.6
2004-10-01	55.3
2005-01-01	57
2005-04-01	42.9
2005-07-01	45.2
2005-10-01	51.7
2006-01-01	53.4
2006-04-01	44
2006-07-01	42.8
2006-10-01	52.3
2007-01-01	52.6
2007-04-01	43.4
2007-07-01	43
2007-10-01	50.1
2008-01-01	50.3
2008-04-01	41.8
2008-07-01	43.5
2008-10-01	52.1
2009-01-01	51.7
2009-04-01	42.7
2009-07-01	47.9
2009-10-01	53.8
2010-01-01	52
2010-04-01	44.2
2010-07-01	45.4
2010-10-01	53.1
2011-01-01	50.6
2011-04-01	42.9
2011-07-01	44.3
2011-10-01	51
2012-01-01	49.9
2012-04-01	42
2012-07-01	43.3
2012-10-01	51
2013-01-01	48.9
2013-04-01	40.8
2013-07-01	41.8
2013-10-01	47.9
2014-01-01	47.5
2014-04-01	40.4
2014-07-01	39.3
2014-10-01	48.6
2015-01-01	46.1
2015-04-01	39.4
2015-07-01	40.2
2015-10-01	48.2
2016-01-01	46.0
2016-04-01	39.3
2016-07-01	43.3
2016-10-01	49.2
2017-01-01	47.0
2017-04-01	41.3
2017-07-01	41.9
2017-10-01	48.3
2018-01-01	48.2
2018-04-01	40.7