Quarter	Percent
1998-01-01	42.5
1999-01-01	43.9
1999-04-01	43.3
1999-07-01	41.7
1999-10-01	39.8
2000-01-01	44.5
2000-04-01	44.3
2000-07-01	42.7
2000-10-01	42.9
2001-01-01	40.2
2001-04-01	43.1
2001-07-01	42.3
2001-10-01	42.9
2002-01-01	40.8
2002-04-01	42.6
2002-07-01	42.3
2002-10-01	42.9
2003-01-01	42.5
2003-04-01	43.3
2003-07-01	42.8
2003-10-01	43.1
2004-01-01	37
2004-04-01	39.4
2004-07-01	38.8
2004-10-01	38.7
2005-01-01	39.1
2005-04-01	40.2
2005-07-01	40.3
2005-10-01	41.9
2006-01-01	43.3
2006-04-01	44.4
2006-07-01	44.2
2006-10-01	44.4
2007-01-01	45.2
2007-04-01	48.9
2007-07-01	48.7
2007-10-01	47.6
2008-01-01	50.3
2008-04-01	50.9
2008-07-01	48.9
2008-10-01	49.4
2009-01-01	48.9
2009-04-01	50.8
2009-07-01	51.5
2009-10-01	51
2010-01-01	50.6
2010-04-01	51.6
2010-07-01	52.2
2010-10-01	51.1
2011-01-01	49.7
2011-04-01	50.8
2011-07-01	50.7
2011-10-01	50.2
2012-01-01	49.4
2012-04-01	52.4
2012-07-01	53.6
2012-10-01	53.6
2013-01-01	53
2013-04-01	55.5
2013-07-01	55.6
2013-10-01	56.2
2014-01-01	55.1
2014-04-01	57.5
2014-07-01	56.8
2014-10-01	57.8
2015-01-01	56.5
2015-04-01	56.5
2015-07-01	57.7
2015-10-01	58.8
2016-01-01	60.0
2016-04-01	61.5
2016-07-01	61.6
2016-10-01	61.5
2017-01-01	61.6
2017-04-01	63.0
2017-07-01	63.0
2017-10-01	64.5
2018-01-01	64.9
2018-04-01	65.9