Quarter	Percent
1998-04-01	67.4
1999-01-01	65.5
1999-04-01	67.1
1999-07-01	60.7
1999-10-01	63.9
2000-01-01	67.3
2000-04-01	64.3
2000-07-01	62.4
2000-10-01	64.8
2001-01-01	66
2001-04-01	66.4
2001-07-01	59.6
2001-10-01	65
2002-01-01	66.7
2002-04-01	66.2
2002-07-01	61.5
2002-10-01	62.8
2003-01-01	65.9
2003-04-01	66.5
2003-07-01	64.1
2003-10-01	63.6
2004-01-01	65
2004-04-01	66
2004-07-01	62.7
2004-10-01	65.2
2005-01-01	64.7
2005-04-01	66.8
2005-07-01	64.7
2005-10-01	63.6
2006-01-01	64.6
2006-04-01	67.7
2006-07-01	65
2006-10-01	64
2007-01-01	66.7
2007-04-01	66.9
2007-07-01	65.5
2007-10-01	65.6
2008-01-01	67.1
2008-04-01	68.6
2008-07-01	64.7
2008-10-01	66
2009-01-01	69
2009-04-01	68.2
2009-07-01	66.5
2009-10-01	66.5
2010-01-01	68.4
2010-04-01	69.2
2010-07-01	65.3
2010-10-01	67
2011-01-01	68.1
2011-04-01	70
2011-07-01	67.1
2011-10-01	66.8
2012-01-01	69.1
2012-04-01	70.2
2012-07-01	68.1
2012-10-01	66.7
2013-01-01	70.2
2013-04-01	69.3
2013-07-01	67.4
2013-10-01	69.1
2014-01-01	70.7
2014-04-01	71.2
2014-07-01	68.3
2014-10-01	69.1
2015-01-01	69.6
2015-04-01	71.4
2015-07-01	69.4
2015-10-01	69.7
2016-01-01	71.2
2016-04-01	72.3
2016-07-01	71.3
2016-10-01	71.4
2017-01-01	73.3
2017-04-01	74.2
2017-07-01	68.8
2017-10-01	71.3
2018-01-01	72.3
2018-04-01	72.4