Quarter	Percent
1986-01-01	51.8
1986-04-01	51.7
1986-07-01	51.9
1986-10-01	52.4
1987-01-01	52.2
1987-04-01	52.3
1987-07-01	52.2
1987-10-01	53.0
1988-01-01	51.7
1988-04-01	51.2
1988-07-01	50.5
1988-10-01	51
1989-01-01	49.4
1989-04-01	48.9
1989-07-01	49
1989-10-01	49.7
1990-01-01	49.6
1990-04-01	50.5
1990-07-01	49.8
1990-10-01	49.9
1991-01-01	49.2
1991-04-01	49.1
1991-07-01	48.7
1991-10-01	48.9
1992-01-01	48.3
1992-04-01	49
1992-07-01	48.5
1992-10-01	49.2
1993-01-01	48.5
1993-04-01	48.6
1993-07-01	49.4
1993-10-01	49.9
1994-01-01	49.9
1994-04-01	50.3
1994-07-01	50.8
1994-10-01	52
1995-01-01	51.5
1995-04-01	51.9
1995-07-01	52.4
1995-10-01	53
1996-01-01	52.9
1996-04-01	53.6
1996-07-01	54.1
1996-10-01	53.7
1997-01-01	53
1997-04-01	53.2
1997-07-01	53.1
1997-10-01	53.3
1998-01-01	52.5
1998-04-01	52.3
1998-07-01	52.8
1998-10-01	53.0
1999-01-01	53.1
1999-04-01	53.1
1999-07-01	53.4
1999-10-01	54.2
2000-01-01	53.4
2000-04-01	53.0
2000-07-01	54.3
2000-10-01	55.1
2001-01-01	54.4
2001-04-01	55.1
2001-07-01	54.8
2001-10-01	56.2
2002-01-01	55.5
2002-04-01	55.6
2002-07-01	55.6
2002-10-01	56.4
2003-01-01	55.5
2003-04-01	55.7
2003-07-01	56.8
2003-10-01	57.1
2004-01-01	56.4
2004-04-01	55.9
2004-07-01	57.2
2004-10-01	58.8
2005-01-01	57.7
2005-04-01	57.9
2005-07-01	58.7
2005-10-01	58.8
2006-01-01	58.7
2006-04-01	59.0
2006-07-01	58.5
2006-10-01	58.7
2007-01-01	59.0
2007-04-01	59.2
2007-07-01	58.6
2007-10-01	60.3
2008-01-01	58.2
2008-04-01	59.4
2008-07-01	59.7
2008-10-01	60.4
2009-01-01	58.7
2009-04-01	58.1
2009-07-01	58.1
2009-10-01	58.3
2010-01-01	57.7
2010-04-01	57.5
2010-07-01	57.5
2010-10-01	58.1
2011-01-01	58.2
2011-04-01	58.2
2011-07-01	57.9
2011-10-01	58.8
2012-01-01	58.2
2012-04-01	58.3
2012-07-01	58.1
2012-10-01	57.3
2013-01-01	58.2
2013-04-01	58
2013-07-01	58.6
2013-10-01	59.4
2014-01-01	59.4
2014-04-01	58.7
2014-07-01	59.4
2014-10-01	60.7
2015-01-01	60.2
2015-04-01	59.4
2015-07-01	58.9
2015-10-01	60.1
2016-01-01	60.2
2016-04-01	60.8
2016-07-01	60.9
2016-10-01	62.1
2017-01-01	61.7
2017-04-01	61.1
2017-07-01	62.1
2017-10-01	63.0
2018-01-01	62.7
2018-04-01	62.6
2018-07-01	63.2