Month	Percent
1997-01-01	17.95
1997-02-01	17.43
1997-03-01	16.76
1997-04-01	16.26
1997-05-01	16.26
1997-06-01	16.21
1997-07-01	16.14
1997-08-01	15.95
1997-09-01	15.67
1997-10-01	15.46
1997-11-01	15.62
1997-12-01	15.67
1998-01-01	15.53
1998-02-01	15.36
1998-03-01	15.19
1998-04-01	15.32
1998-05-01	15.94
1998-06-01	16.00
1998-07-01	16.16
1998-08-01	16.20
1998-09-01	16.45
1998-10-01	17.64
1998-11-01	18.07
1998-12-01	18.24
1999-01-01	18.01
1999-02-01	18.43
1999-03-01	18.34
1999-04-01	18.36
1999-05-01	18.52
1999-06-01	18.35
1999-07-01	17.66
1999-08-01	17.43
1999-09-01	16.84
1999-10-01	16.74
1999-11-01	16.59
1999-12-01	16.53
2000-01-01	15.78
2000-02-01	15.51
2000-03-01	15.15
2000-04-01	15.15
2000-05-01	15.05
2000-06-01	15.54
2000-07-01	15.47
2000-08-01	15.87
2000-09-01	15.75
2000-10-01	15.15
2000-11-01	15.05
2000-12-01	14.85
2001-01-01	14.60
2001-02-01	14.18
2001-03-01	14.09
2001-04-01	14.01
2001-05-01	13.57
2001-06-01	13.50
2001-07-01	13.48
2001-08-01	13.16
2001-09-01	13.13
2001-10-01	13.06
2001-11-01	13.05
2001-12-01	13.88
2002-01-01	14.06
2002-02-01	14.48
2002-03-01	14.67
2002-04-01	14.74
2002-05-01	14.71
2002-06-01	14.70
2002-07-01	14.54
2002-08-01	14.54
2002-09-01	14.63
2002-10-01	14.48
2002-11-01	14.53
2002-12-01	14.51
2003-01-01	14.05
2003-02-01	14.08
2003-03-01	14.06
2003-04-01	13.91
2003-05-01	13.57
2003-06-01	13.31
2003-07-01	12.93
2003-08-01	12.73
2003-09-01	12.49
2003-10-01	12.21
2003-11-01	12.22
2003-12-01	12.26
2004-01-01	12.23
2004-02-01	12.06
2004-03-01	12.08
2004-04-01	12.08
2004-05-01	12.10
2004-06-01	12.22
2004-07-01	12.23
2004-08-01	12.21
2004-09-01	12.27
2004-10-01	12.30
2004-11-01	12.31
2004-12-01	12.32
2005-01-01	12.42
2005-02-01	12.54
2005-03-01	12.62
2005-04-01	12.56
2005-05-01	12.82
2005-06-01	12.80
2005-07-01	12.76
2005-08-01	12.67
2005-09-01	12.71
2005-10-01	12.70
2005-11-01	12.76
2005-12-01	12.91
2006-01-01	12.91
2006-02-01	12.92
2006-03-01	12.89
2006-04-01	12.90
2006-05-01	11.57
2006-06-01	11.59
2006-07-01	11.63
2006-08-01	11.64
2006-09-01	11.41
2006-10-01	11.05
2006-11-01	10.43
2006-12-01	10.21
2007-01-01	9.14
2007-02-01	7.70
2007-03-01	7.34
2007-04-01	6.91
2007-05-01	6.66
2007-06-01	6.64
2007-07-01	6.60
2007-08-01	6.66
2007-09-01	6.65
2007-10-01	6.48
2007-11-01	6.38
2007-12-01	6.40
2008-01-01	6.22
2008-02-01	3.67
2008-03-01	3.44
2008-04-01	3.09
2008-05-01	3.09
2008-06-01	3.44
2008-07-01	3.85
2008-08-01	5.12
2008-09-01	6.32
2008-10-01	6.96
2008-11-01	7.95
2008-12-01	7.99
2009-01-01	8.03
2009-02-01	8.48
2009-03-01	8.43
2009-04-01	8.47
2009-05-01	8.17
2009-06-01	8.15
2009-07-01	9.18
2009-08-01	9.09
2009-09-01	8.95
2009-10-01	8.55
2009-11-01	8.04
2009-12-01	6.66
2010-01-01	6.44
2010-02-01	6.39
2010-03-01	6.40
2010-04-01	6.34
2010-05-01	6.46
2010-06-01	6.26
2010-07-01	6.45
2010-08-01	6.00
2010-09-01	5.57
2010-10-01	5.61
2010-11-01	5.68
2010-12-01	5.67
2011-01-01	5.67
2011-02-01	5.67
2011-03-01	5.60
2011-04-01	5.53
2011-05-01	5.38
2011-06-01	5.16
2011-07-01	5.05
2011-08-01	5.04
2011-09-01	5.17
2011-10-01	5.14
2011-11-01	5.12
2011-12-01	5.17
2012-01-01	5.27
2012-02-01	5.71
2012-03-01	5.86
2012-04-01	5.93
2012-05-01	5.93
2012-06-01	5.93
2012-07-01	6.11
2012-08-01	6.28
2012-09-01	6.28
2012-10-01	6.19
2012-11-01	5.94
2012-12-01	5.94
2013-01-01	5.73
2013-02-01	5.19
2013-03-01	5.13
2013-04-01	5.00
2013-05-01	4.79
2013-06-01	4.74
2013-07-01	4.50
2013-08-01	4.32
2013-09-01	4.33
2013-10-01	4.29
2013-11-01	4.28
2013-12-01	4.13
2014-01-01	4.03
2014-02-01	3.94
2014-03-01	3.97
2014-04-01	3.98
2014-05-01	4.25
2014-06-01	4.30
2014-07-01	4.30
2014-08-01	4.33
2014-09-01	4.33
2014-10-01	4.36
2014-11-01	4.36
2014-12-01	4.36
2015-01-01	4.37
2015-02-01	4.22
2015-03-01	4.20
2015-04-01	4.18
2015-05-01	4.28
2015-06-01	4.35
2015-07-01	4.32
2015-08-01	4.10
2015-09-01	4.04
2015-10-01	3.89
2015-11-01	3.56
2015-12-01	3.49
2016-01-01	3.45
2016-02-01	3.43
2016-03-01	3.49
2016-04-01	3.48
2016-05-01	3.42
2016-06-01	3.39
2016-07-01	3.33
2016-08-01	3.35
2016-09-01	3.36
2016-10-01	3.35
2016-11-01	3.33
2016-12-01	3.33
2017-01-01	3.40
2017-02-01	3.45
2017-03-01	3.46
2017-04-01	3.46
2017-05-01	3.70
2017-06-01	4.78
2017-07-01	5.19
2017-08-01	5.19
2017-09-01	5.24
2017-10-01	5.18
2017-11-01	5.18
2017-12-01	5.23
2018-01-01	5.38
2018-02-01	5.45
2018-03-01	5.42
2018-04-01	5.27
2018-05-01	5.30
2018-06-01	5.25
2018-07-01	5.25
2018-08-01	5.03
2018-09-01	5.12
