Quarter	Percent
2005-01-01	79.5
2005-04-01	79.7
2005-07-01	78.8
2005-10-01	79.7
2006-01-01	77.5
2006-04-01	75.3
2006-07-01	76.7
2006-10-01	77.1
2007-01-01	77.2
2007-04-01	77.2
2007-07-01	76.7
2007-10-01	79.5
2008-01-01	76.3
2008-04-01	76.8
2008-07-01	72.1
2008-10-01	73.6
2009-01-01	75.6
2009-04-01	74.7
2009-07-01	72.9
2009-10-01	73.5
2010-01-01	74.7
2010-04-01	77.7
2010-07-01	73.5
2010-10-01	72.4
2011-01-01	76.1
2011-04-01	77.3
2011-07-01	74.1
2011-10-01	76.2
2012-01-01	75.2
2012-04-01	74.3
2012-07-01	72.7
2012-10-01	73.5
2013-01-01	74.1
2013-04-01	73.4
2013-07-01	70.6
2013-10-01	73.8
2014-01-01	70.9
2014-04-01	71.3
2014-07-01	69.7
2014-10-01	69.8
2015-01-01	71.5
2015-04-01	70.0
2015-07-01	68.8
2015-10-01	66.5
2016-01-01	68.0
2016-04-01	70.3
2016-07-01	66.3
2016-10-01	68.0
2017-01-01	70.1
2017-04-01	65.8
2017-07-01	67.0
2017-10-01	68.3
2018-01-01	67.6
2018-04-01	67.4