Quarter	Percent
1999-04-01	67.7
2000-01-01	70.7
2000-04-01	72.2
2000-07-01	74.6
2000-10-01	74.2
2001-01-01	73.1
2001-04-01	73.6
2001-07-01	75.1
2001-10-01	73.4
2002-01-01	72.3
2002-04-01	73.9
2002-07-01	75
2002-10-01	73.7
2003-01-01	72.7
2003-04-01	73.6
2003-07-01	73.8
2003-10-01	71.7
2004-01-01	71.6
2004-04-01	72
2004-07-01	71.9
2004-10-01	70.8
2005-01-01	70.5
2005-04-01	71.3
2005-07-01	72
2005-10-01	70.3
2006-01-01	69.8
2006-04-01	70.4
2006-07-01	71.9
2006-10-01	71
2007-01-01	71.4
2007-04-01	73
2007-07-01	74.5
2007-10-01	72.1
2008-01-01	72.1
2008-04-01	73.4
2008-07-01	74.2
2008-10-01	73
2009-01-01	72.9
2009-04-01	73
2009-07-01	73.6
2009-10-01	71.7
2010-01-01	68.6
2010-04-01	69.3
2010-07-01	70.1
2010-10-01	68.1
2011-01-01	66.5
2011-04-01	67.4
2011-07-01	69.5
2011-10-01	69.0
2012-01-01	68.4
2012-04-01	68.9
2012-07-01	70.4
2012-10-01	69.2
2013-01-01	68.4
2013-04-01	69.3
2013-07-01	70.3
2013-10-01	68.8
2014-01-01	66.8
2014-04-01	67.0
2014-07-01	68.3
2014-10-01	67.4
2015-01-01	67.5
2015-04-01	68.9
2015-07-01	69.7
2015-10-01	67.8
2016-01-01	67.2
2016-04-01	68.6
2016-07-01	69.4
2016-10-01	67.6
2017-01-01	67.0
2017-04-01	68.1
2017-07-01	69.9
2017-10-01	68.4
2018-01-01	67.7
2018-04-01	68.7