Month Percent 1986-04-01 44.5 1986-05-01 44.6 1986-06-01 43.9 1986-07-01 42.5 1986-08-01 41.6 1986-09-01 42 1986-10-01 42.5 1986-11-01 42.9 1986-12-01 42.4 1987-01-01 42.6 1987-02-01 42.3 1987-03-01 41.9 1987-04-01 41.5 1987-05-01 40.7 1987-06-01 40 1987-07-01 39.3 1987-08-01 38.8 1987-09-01 39.3 1987-10-01 39.7 1987-11-01 39.7 1987-12-01 39.6 1988-01-01 39.9 1988-02-01 39.8 1988-03-01 39.4 1988-04-01 39.4 1988-05-01 38.7 1988-06-01 38.3 1988-07-01 37.3 1988-08-01 36.8 1988-09-01 36.7 1988-10-01 36.5 1988-11-01 36.2 1988-12-01 35.7 1989-01-01 36 1989-02-01 35.6 1989-03-01 34.6 1989-04-01 33.8 1989-05-01 32.3 1989-06-01 31.8 1989-07-01 31.2 1989-08-01 31.1 1989-09-01 31 1989-10-01 31.6 1989-11-01 31.8 1989-12-01 32 1990-01-01 32 1990-02-01 32.1 1990-03-01 31.4 1990-04-01 30.8 1990-05-01 30 1990-06-01 29.9 1990-07-01 29.6 1990-08-01 29.8 1990-09-01 30 1990-10-01 30.3 1990-11-01 30 1990-12-01 29.8 1991-01-01 29.6 1991-02-01 29.7 1991-03-01 29.4 1991-04-01 29 1991-05-01 28.4 1991-06-01 28.4 1991-07-01 28.2 1991-08-01 28.4 1991-09-01 29.1 1991-10-01 30.1 1991-11-01 29.9 1991-12-01 29.7 1992-01-01 30.1 1992-02-01 30.4 1992-03-01 30.9 1992-04-01 31.3 1992-05-01 30.8 1992-06-01 31.3 1992-07-01 31.3 1992-08-01 31.5 1992-09-01 33.1 1992-10-01 35 1992-11-01 36 1992-12-01 36.6 1993-01-01 37.7 1993-02-01 38.6 1993-03-01 39.7 1993-04-01 39.7 1993-05-01 39.5 1993-06-01 40.9 1993-07-01 41 1993-08-01 41 1993-09-01 42.2 1993-10-01 42.6 1993-11-01 42.8 1993-12-01 42.7 1994-01-01 43.8 1994-02-01 44.1 1994-03-01 43.8 1994-04-01 43.1 1994-05-01 42.3 1994-06-01 42.3 1994-07-01 41.4 1994-08-01 41.1 1994-09-01 41.5 1994-10-01 41.2 1994-11-01 41.5 1994-12-01 41.6 1995-01-01 40.1 1995-02-01 41.1 1995-03-01 41 1995-04-01 39.7 1995-05-01 39.2 1995-06-01 39.4 1995-07-01 38.9 1995-08-01 38.9 1995-09-01 39.9 1995-10-01 39.8 1995-11-01 40.1 1995-12-01 39 1996-01-01 40.2 1996-02-01 40.7 1996-03-01 40.5 1996-04-01 39.5 1996-05-01 38.9 1996-06-01 39.1 1996-07-01 38.6 1996-08-01 38.3 1996-09-01 39.3 1996-10-01 39.1 1996-11-01 39.1 1996-12-01 37.4 1997-01-01 37.8 1997-02-01 38 1997-03-01 37.4 1997-04-01 36.7 1997-05-01 36.1 1997-06-01 36.4 1997-07-01 35.4 1997-08-01 35 1997-09-01 35.9 1997-10-01 35.7 1997-11-01 35.4 1997-12-01 34.1 1998-01-01 34.4 1998-02-01 34.2 1998-03-01 34 1998-04-01 33.1 1998-05-01 32.4 1998-06-01 32.5 1998-07-01 31.5 1998-08-01 31.4 1998-09-01 31.8 1998-10-01 31.8 1998-11-01 31.5 1998-12-01 29.8 1999-01-01 29.6 1999-02-01 28.9 1999-03-01 28.1 1999-04-01 26.8 1999-05-01 25.9 1999-06-01 26.1 1999-07-01 25.2 1999-08-01 25.3 1999-09-01 25.7 1999-10-01 25.6 1999-11-01 25.8 1999-12-01 24.5 2000-01-01 25.5 2000-02-01 25.1 2000-03-01 24.3 2000-04-01 23 2000-05-01 22.2 2000-06-01 22.4 2000-07-01 22.1 2000-08-01 22.5 2000-09-01 23.1 2000-10-01 23.6 2000-11-01 23.4 2000-12-01 21.5 2001-01-01 21.1 2001-02-01 22.1 2001-03-01 21.6 2001-04-01 20.5 2001-05-01 20.8 2001-06-01 20.8 2001-07-01 20.3 2001-08-01 20.8 2001-09-01 21.1 2001-10-01 21.5 2001-11-01 21.6 2001-12-01 20.8 2002-01-01 21.8 2002-02-01 22.5 2002-03-01 21.9 2002-04-01 21.6 2002-05-01 21.2 2002-06-01 21.7 2002-07-01 21.6 2002-08-01 21.8 2002-09-01 22.7 2002-10-01 23.4 2002-11-01 23.5 2002-12-01 22.6 2003-01-01 23.4 2003-02-01 23.4 2003-03-01 23.3 2003-04-01 22.6 2003-05-01 21.8 2003-06-01 22.4 2003-07-01 21.9 2003-08-01 21.9 2003-09-01 22.8 2003-10-01 23.3 2003-11-01 23.3 2003-12-01 22.3 2004-01-01 22.8 2004-02-01 22.7 2004-03-01 22.4 2004-04-01 22.8 2004-05-01 22.1 2004-06-01 22.4 2004-07-01 21.5 2004-08-01 21.4 2004-09-01 22 2004-10-01 21.6 2004-11-01 21.6 2004-12-01 20.6 2005-01-01 21.5 2005-02-01 21.9 2005-03-01 21.7 2005-04-01 21.2 2005-05-01 20.2 2005-06-01 19.5 2005-07-01 18.1 2005-08-01 17.7 2005-09-01 18.2 2005-10-01 18.8 2005-11-01 18.9 2005-12-01 18.1 2006-01-01 18.5 2006-02-01 18.7 2006-03-01 19 2006-04-01 18.8 2006-05-01 18.2 2006-06-01 17.6 2006-07-01 16.7 2006-08-01 16.7 2006-09-01 17.3 2006-10-01 18 2006-11-01 18.2 2006-12-01 17.2 2007-01-01 17.5 2007-02-01 17.7 2007-03-01 18 2007-04-01 18.3 2007-05-01 17.9 2007-06-01 18.2 2007-07-01 17.5 2007-08-01 17.8 2007-09-01 18.3 2007-10-01 18.3 2007-11-01 18.9 2007-12-01 18.8 2008-01-01 20.2 2008-02-01 21.2 2008-03-01 21.8 2008-04-01 23.2 2008-05-01 23.7 2008-06-01 23.9 2008-07-01 23.3 2008-08-01 23.8 2008-09-01 25.4 2008-10-01 27.6 2008-11-01 29.3 2008-12-01 30.1 2009-01-01 33.1 2009-02-01 35.8 2009-03-01 37.8 2009-04-01 38.3 2009-05-01 38.3 2009-06-01 37.7 2009-07-01 37.8 2009-08-01 38.3 2009-09-01 39.6 2009-10-01 39.4 2009-11-01 38.9 2009-12-01 38 2010-01-01 39.2 2010-02-01 40.9 2010-03-01 42.1 2010-04-01 42.6 2010-05-01 42.3 2010-06-01 41 2010-07-01 39.9 2010-08-01 40.1 2010-09-01 41.7 2010-10-01 42.7 2010-11-01 43.2 2010-12-01 42.3 2011-01-01 43.7 2011-02-01 45.5 2011-03-01 46.7 2011-04-01 46.5 2011-05-01 46.1 2011-06-01 45 2011-07-01 44.8 2011-08-01 44.8 2011-09-01 47.1 2011-10-01 47.9 2011-11-01 48.6 2011-12-01 47.9 2012-01-01 49.8 2012-02-01 52 2012-03-01 53.2 2012-04-01 53.5 2012-05-01 53.6 2012-06-01 52 2012-07-01 51.4 2012-08-01 51.3 2012-09-01 53.3 2012-10-01 54.7 2012-11-01 55.3 2012-12-01 54.5 2013-01-01 55.9 2013-02-01 57.3 2013-03-01 57.5 2013-04-01 57.2 2013-05-01 56.3 2013-06-01 54.5 2013-07-01 54 2013-08-01 53.4 2013-09-01 54.9 2013-10-01 55.5 2013-11-01 55.5 2013-12-01 53.6 2014-01-01 55.3 2014-02-01 55.6 2014-03-01 55.6 2014-04-01 54.2 2014-05-01 53.4 2014-06-01 51.9 2014-07-01 52.4 2014-08-01 51.9 2014-09-01 52.9 2014-10-01 52.7 2014-11-01 52.1 2014-12-01 50.5 2015-01-01 51.0 2015-02-01 51.5 2015-03-01 51.6 2015-04-01 50.7 2015-05-01 49.6 2015-06-01 47.4 2015-07-01 46.5 2015-08-01 46.0 2015-09-01 47.2 2015-10-01 47.3 2015-11-01 46.5 2015-12-01 44.9 2016-01-01 45.2 2016-02-01 46.8 2016-03-01 47.5 2016-04-01 48.0 2016-05-01 47.0 2016-06-01 44.4 2016-07-01 42.1 2016-08-01 41.1 2016-09-01 42.7 2016-10-01 43.5 2016-11-01 43.9 2016-12-01 41.3 2017-01-01 41.2 2017-02-01 41.7 2017-03-01 42.1 2017-04-01 41.3 2017-05-01 40.0 2017-06-01 37.4 2017-07-01 35.7 2017-08-01 35.0 2017-09-01 37.2 2017-10-01 38.2 2017-11-01 38.0 2017-12-01 36.1 2018-01-01 35.9 2018-02-01 36.6 2018-03-01 36.5 2018-04-01 36.0 2018-05-01 35.0 2018-06-01 33.1 2018-07-01 32.4 2018-08-01 32.3 2018-09-01 34.2