Quarter	Percent
2005-01-01	24.9
2005-04-01	25.3
2005-07-01	25.6
2005-10-01	24.9
2006-01-01	25.9
2006-04-01	26.8
2006-07-01	27.2
2006-10-01	25.3
2007-01-01	25.7
2007-04-01	27.8
2007-07-01	28.3
2007-10-01	26.4
2008-01-01	28.4
2008-04-01	29.5
2008-07-01	32.3
2008-10-01	29.9
2009-01-01	29.6
2009-04-01	30.0
2009-07-01	29.3
2009-10-01	28.3
2010-01-01	28.1
2010-04-01	25.9
2010-07-01	29.0
2010-10-01	30.7
2011-01-01	28.4
2011-04-01	27.5
2011-07-01	29.2
2011-10-01	27.6
2012-01-01	27.0
2012-04-01	28.8
2012-07-01	30.7
2012-10-01	30.7
2013-01-01	30.4
2013-04-01	30.5
2013-07-01	33.7
2013-10-01	31.4
2014-01-01	32.9
2014-04-01	33.7
2014-07-01	35.9
2014-10-01	34.3
2015-01-01	33.0
2015-04-01	33.5
2015-07-01	33.7
2015-10-01	35.2
2016-01-01	34.0
2016-04-01	34.7
2016-07-01	36.9
2016-10-01	35.8
2017-01-01	34.4
2017-04-01	36.3
2017-07-01	35.4
2017-10-01	34.0
2018-01-01	34.9
2018-04-01	34.9