Quarter	Percent
1999-04-01	31.1
2000-04-01	25.7
2001-04-01	19.7
2002-04-01	27.6
2003-01-01	34.2
2003-04-01	15.7
2003-07-01	17.6
2003-10-01	30.7
2004-01-01	36.8
2004-04-01	17.2
2004-07-01	22.9
2004-10-01	35.9
2005-01-01	36.8
2005-04-01	17.7
2005-07-01	19
2005-10-01	29.5
2006-01-01	34.1
2006-04-01	14.2
2006-07-01	17.8
2006-10-01	26
2007-01-01	26.3
2007-04-01	13.3
2007-07-01	15.9
2007-10-01	23.8
2008-01-01	29
2008-04-01	14.5
2008-07-01	17.3
2008-10-01	31.8
2009-01-01	36
2009-04-01	18
2009-07-01	23.3
2009-10-01	39.4
2010-01-01	34
2010-04-01	18.4
2010-07-01	26.3
2010-10-01	35.9
2011-01-01	35.9
2011-04-01	18.4
2011-07-01	24.7
2011-10-01	34.4
2012-01-01	34.9
2012-04-01	15.4
2012-07-01	22.6
2012-10-01	33
2013-01-01	34.3
2013-04-01	17.3
2013-07-01	18.7
2013-10-01	30.6
2014-01-01	28.4
2014-04-01	15.4
2014-07-01	19.4
2014-10-01	26.5
2015-01-01	27.4
2015-04-01	14.0
2015-07-01	16.6
2015-10-01	28.2
2016-01-01	23.1
2016-04-01	11.9
2016-07-01	12.0
2016-10-01	22.7
2017-01-01	22.8
2017-04-01	7.6
2017-07-01	16.5
2017-10-01	24.6
2018-01-01	26.1
2018-04-01	14.3
