Quarter	Percent
2005-01-01	79.5
2005-04-01	80.1
2005-07-01	80.5
2005-10-01	80.0
2006-01-01	79.6
2006-04-01	80.3
2006-07-01	80.6
2006-10-01	80.2
2007-01-01	79.7
2007-04-01	80.3
2007-07-01	80.6
2007-10-01	80.1
2008-01-01	79.7
2008-04-01	80.4
2008-07-01	80.7
2008-10-01	80.0
2009-01-01	79.5
2009-04-01	79.9
2009-07-01	80.0
2009-10-01	79.4
2010-01-01	79.1
2010-04-01	79.7
2010-07-01	79.8
2010-10-01	79.2
2011-01-01	78.9
2011-04-01	79.5
2011-07-01	79.7
2011-10-01	79.3
2012-01-01	78.8
2012-04-01	79.6
2012-07-01	79.8
2012-10-01	79.4
2013-01-01	79.0
2013-04-01	79.6
2013-07-01	79.8
2013-10-01	79.3
2014-01-01	79.1
2014-04-01	79.6
2014-07-01	80.0
2014-10-01	79.5
2015-01-01	79.2
2015-04-01	79.7
2015-07-01	79.9
2015-10-01	79.6
2016-01-01	79.4
2016-04-01	80.0
2016-07-01	80.3
2016-10-01	79.9
2017-01-01	79.6
2017-04-01	80.2