Quarter	Percent
1982-01-01	14.20
1982-04-01	12.50
1982-07-01	11.10
1982-10-01	11.60
1983-01-01	12.66
1983-04-01	11.57
1983-07-01	11.54
1983-10-01	12.74
1984-01-01	13.47
1984-04-01	12.04
1984-07-01	12.09
1984-10-01	12.36
1985-01-01	11.34
1985-04-01	12.77
1985-07-01	11.90
1985-10-01	12.17
1986-01-01	13.49
1986-04-01	14.40
1986-07-01	14.37
1986-10-01	17.97
1987-01-01	14.20
1987-04-01	14.27
1987-07-01	14.04
1987-10-01	14.21
1988-01-01	13.93
1988-04-01	13.14
1988-07-01	12.81
1988-10-01	12.09
1989-01-01	11.39
1989-04-01	10.71
1989-07-01	11.15
1989-10-01	12.42
1990-01-01	12.62
1990-04-01	11.49
1990-07-01	10.89
1990-10-01	11.53
1991-01-01	10.51
1991-04-01	11.63
1991-07-01	10.59
1991-10-01	11.00
1992-01-01	10.12
1992-04-01	10.22
1992-07-01	31.72
1992-10-01	22.94
1993-01-01	8.82
1993-04-01	7.40
1993-07-01	6.29
1993-10-01	6.42
1994-01-01	5.37
1994-04-01	4.98
1994-07-01	5.62
1994-10-01	6.58
1995-01-01	4.99
1995-04-01	5.96
1995-07-01	5.60
1995-10-01	6.65
1996-01-01	5.16
1996-04-01	4.98
1996-07-01	4.95
1996-10-01	4.15
1997-01-01	3.48
1997-04-01	3.50
1997-07-01	3.70
1997-10-01	3.69
1998-01-01	4.01
1998-04-01	4.65
1998-07-01	8.23
1998-10-01	8.83
1999-01-01	7.73
1999-04-01	6.99
1999-07-01	6.34
1999-10-01	5.92
2000-01-01	5.87
2000-04-01	6.45
2000-07-01	7.08
2000-10-01	7.62
2001-01-01	7.34
2001-04-01	7.37
2001-07-01	7.30
2001-10-01	7.11
2002-01-01	6.74
2002-04-01	6.85
2002-07-01	7.21
2002-10-01	7.01
2003-01-01	5.78
2003-04-01	5.07
2003-07-01	3.11
2003-10-01	2.84
2004-01-01	2.14
2004-04-01	2.19
2004-07-01	2.07
2004-10-01	2.06
2005-01-01	2.06
2005-04-01	2.11
2005-07-01	2.31
2005-10-01	2.63
2006-01-01	2.65
2006-04-01	3.15
2006-07-01	3.32
2006-10-01	3.78
2007-01-01	4.27
2007-04-01	4.60
2007-07-01	5.15
2007-10-01	5.54
2008-01-01	5.77
2008-04-01	5.99
2008-07-01	6.26
2008-10-01	4.76
2009-01-01	2.69
2009-04-01	1.75
2009-07-01	1.47
2009-10-01	1.83
2010-01-01	1.96
2010-04-01	2.28
2010-07-01	2.30
2010-10-01	2.08
2011-01-01	2.22
2011-04-01	2.56
2011-07-01	2.69
2011-10-01	1.98
2012-01-01	1.61
2012-04-01	1.56
2012-07-01	1.49
2012-10-01	1.54
2013-01-01	1.55
2013-04-01	1.48
2013-07-01	1.50
2013-10-01	1.55
2014-01-01	1.48
2014-04-01	1.49
2014-07-01	1.50
2014-10-01	1.35
2015-01-01	1.28
2015-04-01	1.15
2015-07-01	0.94
2015-10-01	0.81
2016-01-01	0.67
2016-04-01	0.49
2016-07-01	0.57
2016-10-01	0.51
2017-01-01	0.49
2017-04-01	0.49
2017-07-01	0.51
2017-10-01	0.49
2018-01-01	0.49
2018-04-01	0.50
2018-07-01	0.59