Month Percent 1997-07-01 12.54 1997-08-01 13.77 1997-09-01 13.47 1997-10-01 14.82 1997-11-01 13.04 1997-12-01 10.63 1998-01-01 19.17 1998-02-01 18.23 1998-03-01 14.36 1998-04-01 15.72 1998-05-01 14.75 1998-06-01 14.86 1998-07-01 16.48 1998-08-01 18.65 1998-10-01 18.78 1998-11-01 14.89 1998-12-01 13.49 1999-01-01 12.75 1999-02-01 10.04 1999-03-01 11.09 1999-04-01 13.59 1999-05-01 11.71 1999-06-01 9.28 1999-07-01 9.76 1999-08-01 9.93 1999-09-01 9.91 1999-10-01 10.68 1999-11-01 11.63 1999-12-01 11.09 2000-01-01 10.05 2000-02-01 12.17 2000-03-01 13.43 2000-04-01 11.76 2000-05-01 10.67 2000-06-01 9.72 2000-07-01 9.90 2000-08-01 9.37 2000-09-01 10.32 2000-10-01 11.50 2000-11-01 10.90 2000-12-01 9.30 2001-01-01 8.30 2001-02-01 8.06 2001-03-01 6.14 2001-04-01 8.62 2001-05-01 8.69 2001-06-01 6.74 2001-07-01 6.44 2001-08-01 7.07 2001-09-01 7.18 2001-10-01 6.61 2001-11-01 6.44 2001-12-01 6.51 2002-01-01 6.00 2002-02-01 5.56 2002-03-01 4.73 2002-04-01 4.39 2002-05-01 4.15 2002-06-01 4.03 2002-07-01 3.51 2002-08-01 2.96 2002-09-01 2.99 2002-10-01 3.03 2002-11-01 2.87 2002-12-01 2.88 2003-01-01 2.97 2003-02-01 2.94 2003-03-01 2.65 2003-04-01 2.48 2003-05-01 2.59 2003-06-01 2.78 2003-07-01 2.97 2003-08-01 2.94 2003-09-01 2.84 2003-10-01 2.75 2003-11-01 2.72 2003-12-01 2.58 2004-01-01 1.80 2004-02-01 1.58 2004-03-01 1.57 2004-04-01 1.49 2004-05-01 1.31 2004-06-01 1.53 2004-07-01 1.66 2004-08-01 1.68 2004-09-01 2.33 2004-10-01 2.35 2004-11-01 2.34 2004-12-01 2.32 2005-01-01 2.49 2005-02-01 2.95 2005-03-01 2.83 2005-04-01 2.92 2005-05-01 3.24 2005-06-01 2.85 2005-07-01 3.01 2005-08-01 3.83 2005-09-01 4.25 2005-10-01 4.52 2005-11-01 4.73 2005-12-01 4.75 2006-01-01 4.64 2006-02-01 4.39 2006-03-01 4.48 2006-04-01 4.50 2006-05-01 4.64 2006-06-01 4.82 2006-07-01 4.92 2006-08-01 5.20 2006-09-01 5.21 2006-10-01 4.95 2006-11-01 5.06 2006-12-01 5.10 2007-01-01 5.04 2007-02-01 4.84 2007-03-01 4.61 2007-04-01 4.75 2007-05-01 4.86 2007-06-01 4.75 2007-07-01 4.87 2007-08-01 5.45 2007-09-01 5.50 2007-10-01 5.41 2007-11-01 5.92 2007-12-01 6.15 2008-01-01 6.50 2008-02-01 6.60 2008-03-01 6.61 2008-04-01 6.61 2008-05-01 6.68 2008-06-01 7.32 2008-07-01 7.57 2008-11-01 8.36 2008-12-01 8.18 2009-01-01 6.74 2009-02-01 4.43 2009-03-01 2.62 2009-04-01 1.89 2009-05-01 1.20 2009-06-01 1.08 2009-07-01 0.60 2009-08-01 0.46 2009-09-01 0.49 2009-10-01 0.49 2009-11-01 0.48 2009-12-01 0.48 2010-01-01 0.46 2010-02-01 0.49 2010-03-01 0.50 2010-06-01 1.44 2010-07-01 1.85 2010-08-01 2.47 2010-09-01 2.99 2010-10-01 3.21 2010-11-01 3.26 2010-12-01 3.40 2011-01-01 3.60 2011-02-01 3.88 2011-03-01 4.26 2011-04-01 5.01 2011-05-01 5.37 2011-06-01 5.55 2011-07-01 5.56 2011-08-01 5.35 2011-09-01 5.28 2011-10-01 5.14 2011-11-01 5.11 2012-01-01 4.84 2012-02-01 4.98 2012-03-01 5.07 2012-04-01 5.05 2012-05-01 5.16 2012-09-01 4.96 2013-01-01 5.08 2013-04-01 5.03 2013-05-01 4.98 2013-06-01 4.91 2013-07-01 4.88 2013-09-01 4.75 2014-01-01 4.45 2014-02-01 4.19 2014-03-01 4.04 2014-04-01 3.72 2014-06-01 3.95 2014-07-01 3.77 2015-01-01 2.81 2015-02-01 3.08 2015-03-01 1.53 2015-04-01 3.03 2015-06-01 2.85 2016-01-01 3.50 2016-02-01 3.62 2016-03-01 3.60 2016-04-01 3.50 2016-05-01 3.54 2016-06-01 3.52 2016-07-01 3.50 2016-08-01 3.48 2016-09-01 3.50 2016-10-01 3.48 2017-01-01 3.22 2017-04-01 2.72 2017-05-01 2.54 2017-06-01 2.49 2017-07-01 2.45 2017-08-01 2.47 2017-09-01 2.49 2017-10-01 2.50 2017-11-01 2.49 2018-01-01 2.50 2018-02-01 2.52 2018-03-01 2.62 2018-04-01 2.62 2018-05-01 2.59 2018-06-01 2.63 2018-07-01 2.63 2018-08-01 2.63 2018-09-01 2.63