Quarter	Percent
2005-01-01	50.5
2005-04-01	49.9
2005-07-01	49.6
2005-10-01	49.7
2006-01-01	50.1
2006-04-01	49.6
2006-07-01	49.3
2006-10-01	49.4
2007-01-01	49.9
2007-04-01	49.4
2007-07-01	49.3
2007-10-01	49.2
2008-01-01	49.7
2008-04-01	49.0
2008-07-01	49.0
2008-10-01	49.1
2009-01-01	49.5
2009-04-01	49.0
2009-07-01	48.8
2009-10-01	49.1
2010-01-01	49.4
2010-04-01	48.9
2010-07-01	48.9
2010-10-01	49.2
2011-01-01	49.5
2011-04-01	48.9
2011-07-01	48.9
2011-10-01	48.9
2012-01-01	49.3
2012-04-01	48.6
2012-07-01	48.6
2012-10-01	48.7
2013-01-01	49.1
2013-04-01	48.5
2013-07-01	48.6
2013-10-01	48.6
2014-01-01	49.0
2014-04-01	48.6
2014-07-01	48.6
2014-10-01	48.6
2015-01-01	49.0
2015-04-01	48.5
2015-07-01	48.6
2015-10-01	48.4
2016-01-01	48.6
2016-04-01	48.3
2016-07-01	48.1
2016-10-01	48.3
2017-01-01	48.4
2017-04-01	48.0