Quarter	Percent
1999-01-01	42.3
1999-04-01	42
1999-07-01	44.2
1999-10-01	44
2000-01-01	43
2000-04-01	43.1
2000-07-01	45.4
2000-10-01	44.2
2001-01-01	41.8
2001-04-01	42.4
2001-07-01	44.6
2001-10-01	43.4
2002-01-01	43.4
2002-04-01	43.6
2002-07-01	45.5
2002-10-01	44.2
2003-01-01	43.8
2003-04-01	44.4
2003-07-01	46.5
2003-10-01	44.8
2004-01-01	44.5
2004-04-01	44.9
2004-07-01	46.9
2004-10-01	44.9
2005-01-01	46.5
2005-04-01	47.9
2005-07-01	50
2005-10-01	47.3
2006-01-01	46.9
2006-04-01	48.2
2006-07-01	50
2006-10-01	47.6
2007-01-01	46.4
2007-04-01	47.8
2007-07-01	50.4
2007-10-01	46.9
2008-01-01	46.4
2008-04-01	47.6
2008-07-01	50.1
2008-10-01	46.8
2009-01-01	45.5
2009-04-01	45.2
2009-07-01	46.6
2009-10-01	42.8
2010-01-01	42.2
2010-04-01	43
2010-07-01	44.2
2010-10-01	41.2
2011-01-01	40.4
2011-04-01	41
2011-07-01	43.1
2011-10-01	39.2
2012-01-01	38.5
2012-04-01	39.3
2012-07-01	40.8
2012-10-01	37.5
2013-01-01	37.8
2013-04-01	37.5
2013-07-01	39.2
2013-10-01	36.6
2014-01-01	35.5
2014-04-01	35.3
2014-07-01	37
2014-10-01	35.1
2015-01-01	33.9
2015-04-01	34.8
2015-07-01	36.8
2015-10-01	33.3
2016-01-01	32.3
2016-04-01	33.4
2016-07-01	34.5
2016-10-01	31.9
2017-01-01	31.7
2017-04-01	32.9
2017-07-01	35.8
2017-10-01	33.0
2018-01-01	31.3
2018-04-01	33.0
2018-07-01	35.0