Quarter	Percent
1999-04-01	76.1
2000-04-01	77.7
2001-04-01	76.7
2002-04-01	76.2
2003-01-01	73.3
2003-04-01	75.6
2003-07-01	77.7
2003-10-01	73.1
2004-01-01	73.2
2004-04-01	74.7
2004-07-01	73.8
2004-10-01	72.3
2005-01-01	74.5
2005-04-01	75.8
2005-07-01	74.9
2005-10-01	75.4
2006-01-01	75.1
2006-04-01	76.2
2006-07-01	75.9
2006-10-01	74.3
2007-01-01	75.8
2007-04-01	77.5
2007-07-01	76.3
2007-10-01	74.4
2008-01-01	73.9
2008-04-01	75.9
2008-07-01	75.8
2008-10-01	74.5
2009-01-01	71.2
2009-04-01	71
2009-07-01	73.1
2009-10-01	73
2010-01-01	71.4
2010-04-01	72
2010-07-01	72
2010-10-01	71
2011-01-01	71.2
2011-04-01	73.8
2011-07-01	72.1
2011-10-01	69.6
2012-01-01	70.5
2012-04-01	74
2012-07-01	73.4
2012-10-01	72.9
2013-01-01	71.5
2013-04-01	74
2013-07-01	75.4
2013-10-01	73.9
2014-01-01	72.5
2014-04-01	75.4
2014-07-01	76.1
2014-10-01	75.5
2015-01-01	74.9
2015-04-01	76.9
2015-07-01	76.5
2015-10-01	77.4
2016-01-01	75.9
2016-04-01	77.8
2016-07-01	78.4
2016-10-01	77.2
2017-01-01	77.1
2017-04-01	77.2
2017-07-01	76.2
2017-10-01	76.5
2018-01-01	75.3
2018-04-01	76.1