Month Percent 2010-06-30 -9 2010-07-31 -8.6 2010-08-31 -9.3 2010-09-30 -8.3 2010-10-31 -8.6 2010-11-30 -9.2 2010-12-31 -8.2 2011-01-31 -6.3 2011-02-28 -7.3 2011-03-31 -6.3 2011-04-30 -6.4 2011-05-31 -7.5 2011-06-30 -8 2011-07-31 -6.6 2011-08-31 -5.9 2011-09-30 -4.8 2011-10-31 -3.6 2011-11-30 -2.9 2011-12-31 -3.6 2012-01-31 -4.3 2012-02-29 -5.1 2012-03-31 -4.5 2012-04-30 -5.9 2012-05-31 -5.2 2012-06-30 -4.3 2012-07-31 -4.5 2012-08-31 -5 2012-09-30 -4.9 2012-10-31 -5.5 2012-11-30 -6.6 2012-12-31 -7.3 2013-01-31 -6.6 2013-02-28 -6.2