Quarter	Percent
1999-04-01	67.4
2000-01-01	71.4
2000-04-01	73.4
2000-07-01	75.1
2000-10-01	75.1
2001-01-01	74.2
2001-04-01	74.7
2001-07-01	75.4
2001-10-01	73.6
2002-01-01	73.5
2002-04-01	75.1
2002-07-01	75.2
2002-10-01	74.1
2003-01-01	72.9
2003-04-01	74
2003-07-01	74.2
2003-10-01	73
2004-01-01	72.2
2004-04-01	72.2
2004-07-01	72.4
2004-10-01	71.2
2005-01-01	71.2
2005-04-01	71.7
2005-07-01	71.8
2005-10-01	70.3
2006-01-01	70
2006-04-01	70.9
2006-07-01	73.1
2006-10-01	72.1
2007-01-01	72.1
2007-04-01	73.6
2007-07-01	74.5
2007-10-01	72.1
2008-01-01	73.1
2008-04-01	74.1
2008-07-01	74.2
2008-10-01	73.5
2009-01-01	73
2009-04-01	73
2009-07-01	73.5
2009-10-01	71.3
2010-01-01	68.4
2010-04-01	68.9
2010-07-01	69.5
2010-10-01	67.7
2011-01-01	66.0
2011-04-01	66.4
2011-07-01	68.2
2011-10-01	67.3
2012-01-01	66.8
2012-04-01	67.3
2012-07-01	68.8
2012-10-01	68.0
2013-01-01	67.7
2013-04-01	68.4
2013-07-01	69.3
2013-10-01	68.2
2014-01-01	66.8
2014-04-01	66.9
2014-07-01	68.0
2014-10-01	66.3
2015-01-01	66.8
2015-04-01	68.0
2015-07-01	68.9
2015-10-01	66.5
2016-01-01	66.7
2016-04-01	67.6
2016-07-01	68.4
2016-10-01	66.2
2017-01-01	65.6
2017-04-01	66.7
2017-07-01	68.6
2017-10-01	67.2
2018-01-01	66.9
2018-04-01	67.6