Quarter	Percent
1999-04-01	44
2000-04-01	45.3
2001-04-01	46
2002-04-01	47.4
2003-01-01	47.2
2003-04-01	47.2
2003-07-01	47.2
2003-10-01	47.2
2004-01-01	49
2004-04-01	49
2004-07-01	49
2004-10-01	49
2005-01-01	50
2005-04-01	50
2005-07-01	50
2005-10-01	50
2006-01-01	52.4
2006-04-01	52.4
2006-07-01	52.4
2006-10-01	52.4
2007-01-01	53.3
2007-04-01	50.9
2007-07-01	54
2007-10-01	54.9
2008-01-01	51.6
2008-04-01	53
2008-07-01	51.5
2008-10-01	51.1
2009-01-01	54.3
2009-04-01	53.2
2009-07-01	53
2009-10-01	52.8
2010-01-01	53.1
2010-04-01	52.5
2010-07-01	53.7
2010-10-01	53.7
2011-01-01	54.8
2011-04-01	52.6
2011-07-01	53.2
2011-10-01	52.9
2012-01-01	54.6
2012-04-01	54.3
2012-07-01	57
2012-10-01	55.5
2013-01-01	55.9
2013-04-01	56.1
2013-07-01	55.4
2013-10-01	55.9
2014-01-01	56.6
2014-04-01	56.5
2014-07-01	56.9
2014-10-01	58
2015-01-01	60.7
2015-04-01	60.1
2015-07-01	59.4
2015-10-01	58.9
2016-01-01	58.3
2016-04-01	58.0
2016-07-01	59.3
2016-10-01	59.5
2017-01-01	58.6
2017-04-01	58.7
2017-07-01	61.7
2017-10-01	59.7
2018-01-01	61.4
2018-04-01	60.1