Quarter	Percent
1999-04-01	62
2000-04-01	64.9
2001-04-01	65
2002-04-01	66.7
2003-01-01	66.5
2003-04-01	66.5
2003-07-01	66.5
2003-10-01	66.5
2004-01-01	70.4
2004-04-01	70.4
2004-07-01	70.4
2004-10-01	70.4
2005-01-01	72.2
2005-04-01	72.2
2005-07-01	72.2
2005-10-01	72.2
2006-01-01	73.8
2006-04-01	73.8
2006-07-01	73.8
2006-10-01	73.8
2007-01-01	75.4
2007-04-01	72.9
2007-07-01	73.9
2007-10-01	76.6
2008-01-01	72.7
2008-04-01	74.2
2008-07-01	72.5
2008-10-01	72.4
2009-01-01	77.5
2009-04-01	74.2
2009-07-01	75.4
2009-10-01	74
2010-01-01	77.9
2010-04-01	74.1
2010-07-01	77
2010-10-01	76.6
2011-01-01	78.7
2011-04-01	77
2011-07-01	75.9
2011-10-01	76.9
2012-01-01	78.3
2012-04-01	78.3
2012-07-01	80.5
2012-10-01	79.6
2013-01-01	81.1
2013-04-01	80
2013-07-01	80.1
2013-10-01	80.9
2014-01-01	79.1
2014-04-01	81.3
2014-07-01	80.3
2014-10-01	83.1
2015-01-01	81.6
2015-04-01	82.3
2015-07-01	80.4
2015-10-01	81.0
2016-01-01	80.9
2016-04-01	80.1
2016-07-01	80.6
2016-10-01	82.5
2017-01-01	83.8
2017-04-01	84.2
2017-07-01	85.3
2017-10-01	82.7
2018-01-01	85.7
2018-04-01	84.2