Quarter	Percent
2000-04-01	24.1
2001-04-01	24.7
2002-04-01	26.1
2003-04-01	27.8
2004-04-01	28.7
2005-01-01	31.0
2005-04-01	31.7
2005-07-01	31.6
2005-10-01	32.2
2006-01-01	32.5
2006-04-01	33.0
2006-07-01	33.2
2006-10-01	33.7
2007-01-01	33.9
2007-04-01	35.3
2007-07-01	34.8
2007-10-01	35.1
2008-01-01	35.1
2008-04-01	36.1
2008-07-01	36.2
2008-10-01	36.3
2009-01-01	36.7
2009-04-01	37.7
2009-07-01	37.2
2009-10-01	37.4
2010-01-01	37.9
2010-04-01	38.1
2010-07-01	38.4
2010-10-01	38.5
2011-01-01	39.1
2011-04-01	40
2011-07-01	40.4
2011-10-01	40.6
2012-01-01	41.1
2012-04-01	41.8
2012-07-01	42.4
2012-10-01	42.4
2013-01-01	42.7
2013-04-01	43.4
2013-07-01	44.1
2013-10-01	44.4
2014-01-01	44.6
2014-04-01	45.6
2014-07-01	46.1
2014-10-01	46.4
2015-01-01	46.6
2015-04-01	47.5
2015-07-01	47.6
2015-10-01	47.9
2016-01-01	48.6
2016-04-01	49.4
2016-07-01	49.6
2016-10-01	50.0
2017-01-01	50.5
2017-04-01	51.4
2017-07-01	51.4
2017-10-01	52.0
2018-01-01	52.3
2018-04-01	52.7