Quarter	Percent
1999-01-01	46.5
1999-04-01	46.4
1999-07-01	48.5
1999-10-01	47.5
2000-01-01	46.5
2000-04-01	46.7
2000-07-01	50.1
2000-10-01	48.8
2001-01-01	46.6
2001-04-01	47.4
2001-07-01	50.2
2001-10-01	48.7
2002-01-01	48.5
2002-04-01	48.6
2002-07-01	50.6
2002-10-01	49
2003-01-01	48.6
2003-04-01	49.3
2003-07-01	51.7
2003-10-01	50.1
2004-01-01	49.6
2004-04-01	49.8
2004-07-01	52.2
2004-10-01	50
2005-01-01	51.6
2005-04-01	52.1
2005-07-01	54.7
2005-10-01	51.8
2006-01-01	50.8
2006-04-01	51.7
2006-07-01	54.6
2006-10-01	51.7
2007-01-01	51.1
2007-04-01	52.4
2007-07-01	54.3
2007-10-01	50.8
2008-01-01	50.7
2008-04-01	51
2008-07-01	54.1
2008-10-01	50.1
2009-01-01	48.9
2009-04-01	48.7
2009-07-01	49.4
2009-10-01	45.8
2010-01-01	44.8
2010-04-01	45.9
2010-07-01	46
2010-10-01	43.2
2011-01-01	42.2
2011-04-01	42.5
2011-07-01	44.7
2011-10-01	40.8
2012-01-01	39.6
2012-04-01	40.4
2012-07-01	42.5
2012-10-01	38.9
2013-01-01	39.5
2013-04-01	39.6
2013-07-01	40.9
2013-10-01	38.3
2014-01-01	37.2
2014-04-01	37.2
2014-07-01	38.9
2014-10-01	36
2015-01-01	35.7
2015-04-01	35.9
2015-07-01	38.0
2015-10-01	35.1
2016-01-01	34.2
2016-04-01	35.2
2016-07-01	35.8
2016-10-01	33.8
2017-01-01	33.6
2017-04-01	34.6
2017-07-01	38.0
2017-10-01	34.2
2018-01-01	33.5
2018-04-01	35.3
2018-07-01	37.4