Quarter	Percent
1999-04-01	64.7
2000-01-01	60.8
2000-04-01	66
2000-07-01	67.9
2000-10-01	62.8
2001-01-01	59.1
2001-04-01	66.1
2001-07-01	65.6
2001-10-01	62.3
2002-01-01	61.6
2002-04-01	65.5
2002-07-01	66.7
2002-10-01	62.3
2003-01-01	59.1
2003-04-01	63.7
2003-07-01	64.4
2003-10-01	60.7
2004-01-01	58.1
2004-04-01	63
2004-07-01	64.6
2004-10-01	60.7
2005-01-01	56.1
2005-04-01	61.7
2005-07-01	63.7
2005-10-01	59.9
2006-01-01	55.4
2006-04-01	58.9
2006-07-01	60.4
2006-10-01	55.1
2007-01-01	55.7
2007-04-01	59.7
2007-07-01	61.1
2007-10-01	58.7
2008-01-01	61.3
2008-04-01	64.3
2008-07-01	63.3
2008-10-01	59
2009-01-01	57.6
2009-04-01	60.5
2009-07-01	58.7
2009-10-01	54.8
2010-01-01	55.6
2010-04-01	59.1
2010-07-01	56.8
2010-10-01	55.5
2011-01-01	53.9
2011-04-01	55.9
2011-07-01	57.5
2011-10-01	55.2
2012-01-01	55.1
2012-04-01	58.5
2012-07-01	58.4
2012-10-01	56.1
2013-01-01	57.2
2013-04-01	57.8
2013-07-01	58
2013-10-01	55.1
2014-01-01	53.2
2014-04-01	55.4
2014-07-01	55.4
2014-10-01	53.6
2015-01-01	54.0
2015-04-01	58.0
2015-07-01	58.1
2015-10-01	53.5
2016-01-01	54.4
2016-04-01	55.1
2016-07-01	56.4
2016-10-01	52.4
2017-01-01	51.9
2017-04-01	54.7
2017-07-01	55.6
2017-10-01	52.8
2018-01-01	52.1
2018-04-01	55.6