Quarter	Percent
1999-01-01	57.7
1999-04-01	58
1999-07-01	55.8
1999-10-01	56
2000-01-01	57
2000-04-01	56.9
2000-07-01	54.6
2000-10-01	55.8
2001-01-01	58.2
2001-04-01	57.6
2001-07-01	55.4
2001-10-01	56.6
2002-01-01	56.6
2002-04-01	56.4
2002-07-01	54.5
2002-10-01	55.8
2003-01-01	56.2
2003-04-01	55.6
2003-07-01	53.5
2003-10-01	55.2
2004-01-01	55.5
2004-04-01	55.1
2004-07-01	53.1
2004-10-01	55.1
2005-01-01	53.5
2005-04-01	52.1
2005-07-01	50
2005-10-01	52.7
2006-01-01	53.1
2006-04-01	51.8
2006-07-01	50
2006-10-01	52.4
2007-01-01	53.6
2007-04-01	52.2
2007-07-01	49.6
2007-10-01	53.1
2008-01-01	53.6
2008-04-01	52.4
2008-07-01	49.9
2008-10-01	53.2
2009-01-01	54.5
2009-04-01	54.8
2009-07-01	53.4
2009-10-01	57.2
2010-01-01	57.8
2010-04-01	57
2010-07-01	55.8
2010-10-01	58.8
2011-01-01	59.6
2011-04-01	59
2011-07-01	56.9
2011-10-01	60.8
2012-01-01	61.5
2012-04-01	60.7
2012-07-01	59.2
2012-10-01	62.5
2013-01-01	62.2
2013-04-01	62.5
2013-07-01	60.8
2013-10-01	63.4
2014-01-01	64.5
2014-04-01	64.7
2014-07-01	63
2014-10-01	64.9
2015-01-01	66.1
2015-04-01	65.2
2015-07-01	63.2
2015-10-01	66.7
2016-01-01	67.7
2016-04-01	66.6
2016-07-01	65.5
2016-10-01	68.1
2017-01-01	68.3
2017-04-01	67.1
2017-07-01	64.2
2017-10-01	67.0
2018-01-01	68.7
2018-04-01	67.0
2018-07-01	65.0