Quarter	Percent
2005-01-01	19.5
2005-04-01	18.4
2005-07-01	12.9
2007-01-01	13.4
2007-07-01	10.4
2008-01-01	13.2
2008-07-01	14.7
2008-10-01	17.3
2009-01-01	18.6
2009-04-01	21.6
2009-07-01	26.6
2009-10-01	22.2
2010-01-01	26.6
2010-04-01	32.0
2010-07-01	32.3
2010-10-01	35.1
2011-01-01	27.8
2011-04-01	27.5
2011-07-01	31.7
2011-10-01	30.2
2012-01-01	24.4
2012-04-01	17.7
2012-07-01	23.7
2012-10-01	25.0
2013-01-01	22.3
2013-04-01	20.5
2013-07-01	22.0
2013-10-01	16.4
2014-01-01	22.4
2014-04-01	19.4
2014-07-01	15.0
2014-10-01	18.1
2015-01-01	15.8
2015-04-01	17.2
2015-07-01	18.7
2015-10-01	15.0
2016-01-01	13.3
2016-04-01	14.9
2016-07-01	11.4
2016-10-01	11.1
2017-01-01	13.8
2017-04-01	11.5
2017-07-01	10.2
2017-10-01	11.2
2018-01-01	12.6
2018-04-01	10.3