Quarter	Percent
2000-04-01	40.2
2001-04-01	40.4
2002-04-01	39.8
2003-04-01	38.9
2004-04-01	38.5
2005-01-01	38.1
2005-04-01	38.5
2005-07-01	40.3
2005-10-01	38.8
2006-01-01	38.1
2006-04-01	39.2
2006-07-01	41.3
2006-10-01	39.7
2007-01-01	39.3
2007-04-01	39.9
2007-07-01	41.9
2007-10-01	40.3
2008-01-01	39.8
2008-04-01	40.2
2008-07-01	41.7
2008-10-01	39.3
2009-01-01	37.1
2009-04-01	36.7
2009-07-01	38.0
2009-10-01	35.9
2010-01-01	34.9
2010-04-01	35.8
2010-07-01	37.4
2010-10-01	36.0
2011-01-01	34.7
2011-04-01	35.3
2011-07-01	36.6
2011-10-01	35.1
2012-01-01	33.6
2012-04-01	34.2
2012-07-01	35.8
2012-10-01	34.3
2013-01-01	33.0
2013-04-01	33.7
2013-07-01	35.3
2013-10-01	33.9
2014-01-01	33.1
2014-04-01	33.7
2014-07-01	35.7
2014-10-01	34.5
2015-01-01	33.9
2015-04-01	34.2
2015-07-01	36.2
2015-10-01	35.3
2016-01-01	34.5
2016-04-01	35.2
2016-07-01	36.6
2016-10-01	35.8
2017-01-01	35.0
2017-04-01	36.0
2017-07-01	37.7
2017-10-01	36.7
2018-01-01	36.3
2018-04-01	37.0