Quarter	Percent
1999-01-01	35
1999-04-01	34.9
1999-07-01	35
1999-10-01	35
2000-01-01	35.6
2000-04-01	36.8
2000-07-01	37.6
2000-10-01	38.1
2001-01-01	38.9
2001-04-01	39.1
2001-07-01	39.3
2001-10-01	39.6
2002-01-01	39.4
2002-04-01	39.9
2002-07-01	39.8
2002-10-01	40.4
2003-01-01	40.5
2003-04-01	40.9
2003-07-01	40.7
2003-10-01	41.3
2004-01-01	41.2
2004-04-01	41
2004-07-01	41.1
2004-10-01	41.6
2005-01-01	42.3
2005-04-01	43
2005-07-01	43.1
2005-10-01	43.9
2006-01-01	44.2
2006-04-01	44.2
2006-07-01	43.7
2006-10-01	44.3
2007-01-01	44
2007-04-01	44.7
2007-07-01	44.5
2007-10-01	44.9
2008-01-01	45.2
2008-04-01	45.8
2008-07-01	45.5
2008-10-01	45.4
2009-01-01	44.5
2009-04-01	44.4
2009-07-01	43.6
2009-10-01	43.4
2010-01-01	43.3
2010-04-01	43.4
2010-07-01	43.7
2010-10-01	43.8
2011-01-01	44.1
2011-04-01	44.9
2011-07-01	44.6
2011-10-01	44.3
2012-01-01	43.6
2012-04-01	44.3
2012-07-01	44.2
2012-10-01	43.4
2013-01-01	42.6
2013-04-01	43.1
2013-07-01	43.6
2013-10-01	43.7
2014-01-01	43.3
2014-04-01	44
2014-07-01	44.6
2014-10-01	45.3
2015-01-01	45.9
2015-04-01	46.7
2015-07-01	47.0
2015-10-01	48.0
2016-01-01	48.6
2016-04-01	48.8
2016-07-01	49.5
2016-10-01	49.4
2017-01-01	49.7
2017-04-01	50.5
2017-07-01	50.8
2017-10-01	51.0
2018-01-01	50.9
2018-04-01	52.0
2018-07-01	52.7