Quarter	Percent
1999-04-01	68.7
2000-04-01	73.9
2001-04-01	75.9
2002-04-01	66.8
2003-01-01	60.8
2003-04-01	70.4
2003-07-01	77.8
2003-10-01	60.4
2004-01-01	58.2
2004-04-01	69.7
2004-07-01	74.4
2004-10-01	61.9
2005-01-01	61.7
2005-04-01	75.6
2005-07-01	77.3
2005-10-01	67.3
2006-01-01	65.4
2006-04-01	76
2006-07-01	78.6
2006-10-01	68.2
2007-01-01	69.8
2007-04-01	77.2
2007-07-01	78.9
2007-10-01	71
2008-01-01	68.6
2008-04-01	75.4
2008-07-01	78.3
2008-10-01	64.5
2009-01-01	58
2009-04-01	63.7
2009-07-01	68.5
2009-10-01	55.9
2010-01-01	55.5
2010-04-01	66.4
2010-07-01	67.5
2010-10-01	57.5
2011-01-01	55.9
2011-04-01	69.5
2011-07-01	67.8
2011-10-01	56.8
2012-01-01	56.7
2012-04-01	69.1
2012-07-01	72.6
2012-10-01	63.2
2013-01-01	61.8
2013-04-01	71.3
2013-07-01	76.6
2013-10-01	69.1
2014-01-01	65.7
2014-04-01	73.9
2014-07-01	75.6
2014-10-01	66.8
2015-01-01	67.7
2015-04-01	76.2
2015-07-01	78.7
2015-10-01	69.8
2016-01-01	71.5
2016-04-01	82.1
2016-07-01	83.0
2016-10-01	73.8
2017-01-01	73.3
2017-04-01	82.3
2017-07-01	76.8
2017-10-01	70.7
2018-01-01	71.6
2018-04-01	78.5