Quarter	Percent
1998-01-01	69.3
1998-04-01	70.2
1998-07-01	70.6
1998-10-01	70
1999-01-01	70.1
1999-04-01	70.4
1999-07-01	70.1
1999-10-01	69.2
2000-01-01	69.5
2000-04-01	70.7
2000-07-01	71.1
2000-10-01	70.7
2001-01-01	70.5
2001-04-01	71
2001-07-01	71
2001-10-01	70
2002-01-01	70.2
2002-04-01	71.9
2002-07-01	72.3
2002-10-01	72
2003-01-01	72
2003-04-01	73
2003-07-01	73.5
2003-10-01	72.8
2004-01-01	72.7
2004-04-01	73.7
2004-07-01	73.8
2004-10-01	73.5
2005-01-01	73.3
2005-04-01	74.3
2005-07-01	74.2
2005-10-01	74.2
2006-01-01	74.3
2006-04-01	75.3
2006-07-01	76
2006-10-01	75.4
2007-01-01	74.8
2007-04-01	75.6
2007-07-01	75.9
2007-10-01	75.4
2008-01-01	75.4
2008-04-01	76.4
2008-07-01	76.5
2008-10-01	75.7
2009-01-01	74.9
2009-04-01	75.8
2009-07-01	75.7
2009-10-01	74.7
2010-01-01	73.7
2010-04-01	74
2010-07-01	73.3
2010-10-01	71.6
2011-01-01	70.1
2011-04-01	69.8
2011-07-01	68.9
2011-10-01	66.5
2012-01-01	65
2012-04-01	64.4
2012-07-01	63.6
2012-10-01	62.5
2013-01-01	61.2
2013-04-01	61.7
2013-07-01	61.6
2013-10-01	60.8
2014-01-01	61.2
2014-04-01	62.4
2014-07-01	63.3
2014-10-01	62.7
2015-01-01	62.4
2015-04-01	64.9
2015-07-01	65.6
2015-10-01	65.1
2016-01-01	64.8
2016-04-01	66.8
2016-07-01	66.9
2016-10-01	65.4
2017-01-01	65.5
2017-04-01	68.2
2017-07-01	68.7
2017-10-01	67.1
2018-01-01	67.0
2018-04-01	69.5
