Month Percent 2004-01-31 3.55 2004-02-29 3.75 2004-03-31 3.83 2004-04-30 3.91 2004-05-31 4 2004-06-30 4.06 2004-07-31 4.13 2004-08-31 4.22 2004-09-30 4.35 2004-10-31 4.49 2004-11-30 4.46 2004-12-31 4.48 2005-01-31 4.45 2005-02-28 4.52 2005-03-31 4.53 2005-04-30 4.6 2005-05-31 4.55 2005-06-30 4.55 2005-07-31 4.67 2005-08-31 4.71 2005-09-30 4.72 2005-10-31 4.68 2005-11-30 4.66 2005-12-31 4.66 2006-01-31 4.67 2006-02-28 4.65 2006-03-31 4.52 2006-04-30 4.52 2006-05-31 4.55 2006-06-30 4.56 2006-07-31 4.31 2006-08-31 4.42 2006-09-30 4.44 2006-10-31 4.46 2006-11-30 4.61 2006-12-31 4.63 2007-01-31 4.72 2007-02-28 4.84 2007-03-31 5.07 2007-04-30 5.21 2007-05-31 5.36 2007-06-30 5.5 2007-07-31 5.68 2007-08-31 5.79 2007-09-30 5.82 2007-10-31 5.87 2007-11-30 5.89 2007-12-31 5.92 2008-01-31 5.9 2008-02-29 5.83 2008-03-31 5.77 2008-04-30 5.75 2008-05-31 5.78 2008-06-30 5.75 2008-07-31 5.74 2008-08-31 5.73 2008-09-30 5.71 2008-10-31 5.71 2008-11-30 5.59 2008-12-31 5.27 2009-01-31 5.11 2009-02-28 4.96 2009-03-31 4.81 2009-04-30 4.56 2009-05-31 4.17 2009-06-30 4 2009-07-31 3.86 2009-08-31 3.48 2009-09-30 3.26 2009-10-31 3.15 2009-11-30 2.93 2009-12-31 2.74 2010-01-31 2.73 2010-02-28 2.71 2010-03-31 2.66 2010-04-30 2.65 2010-05-31 2.55 2010-06-30 2.54 2010-07-31 2.42 2010-08-31 2.29 2010-09-30 2.29 2010-10-31 2.3 2010-11-30 2.33 2010-12-31 2.31