Quarter	Millions of US Dollars
1972-01-01	0
1972-04-01	0
1972-07-01	0
1972-10-01	0
1973-01-01	0
1973-04-01	0
1973-07-01	0
1973-10-01	0
1974-01-01	0
1974-04-01	0
1974-07-01	0
1974-10-01	0
1975-01-01	0
1975-04-01	0
1975-07-01	0
1975-10-01	0
1976-01-01	0
1976-04-01	0
1976-07-01	0
1976-10-01	0
1977-01-01	0
1977-04-01	0
1977-07-01	0
1977-10-01	0
1978-01-01	0
1978-04-01	0
1978-07-01	0
1978-10-01	0
1979-01-01	0
1979-04-01	20
1979-07-01	20
1979-10-01	20
1980-01-01	20
1980-04-01	0
1980-07-01	0
1980-10-01	0
1981-01-01	15
1981-04-01	56
1981-07-01	82
1981-10-01	84
1982-01-01	138
1982-04-01	96
1982-07-01	70
1982-10-01	72
1983-01-01	20
1983-04-01	20
1983-07-01	20
1983-10-01	20
1984-01-01	0
1984-04-01	0
1984-07-01	0
1984-10-01	66
1985-01-01	70
1985-04-01	70
1985-07-01	72
1985-10-01	76
1986-01-01	82
1986-04-01	88
1986-07-01	119
1986-10-01	31
1987-01-01	111
1987-04-01	110
1987-07-01	84
1987-10-01	179
1988-01-01	110
1988-04-01	101
1988-07-01	99
1988-10-01	27
1989-01-01	38
1989-04-01	35
1989-07-01	60
1989-10-01	77
1990-01-01	43
1990-04-01	43
1990-07-01	49
1990-10-01	32
1991-01-01	31
1991-04-01	31
1991-07-01	0
1991-10-01	0
1992-01-01	38
1992-04-01	40
1992-07-01	42
1992-10-01	40
1993-01-01	104
1993-04-01	114
1993-07-01	114
1993-10-01	107
1994-01-01	0
1994-04-01	0
1994-07-01	5
1994-10-01	10
1995-01-01	10
1995-04-01	0
1995-07-01	0
1995-10-01	0
1996-01-01	465
1996-04-01	14
1996-07-01	14
1996-10-01	14
1997-01-01	14
1997-04-01	44
1997-07-01	41
1997-10-01	652
1998-01-01	651
1998-04-01	613
1998-07-01	613
1998-10-01	30
1999-01-01	30
1999-04-01	56
1999-07-01	456
1999-10-01	631
2000-01-01	631
2000-04-01	1250
2000-07-01	893
2000-10-01	1492
2001-01-01	2019
2001-04-01	1482
2001-07-01	1656
2001-10-01	1250
2002-01-01	828
2002-04-01	1248
2002-07-01	1536
2002-10-01	1135
2003-01-01	2225
2003-04-01	1747
2003-07-01	1482
2003-10-01	2386
2004-01-01	2354
2004-04-01	3686
2004-07-01	3712
2004-10-01	2916
2005-01-01	1637
2005-04-01	2869
2005-07-01	4067
2005-10-01	4402
2006-01-01	5411
2006-04-01	2819
2006-07-01	1480
2006-10-01	1969
2007-01-01	2738
2007-04-01	4165
2007-07-01	4815
2007-10-01	3947
2008-01-01	3027
2008-04-01	1553
2008-07-01	1124
2008-10-01	3365
2009-01-01	3965
2009-04-01	3765
2009-07-01	3414
2009-10-01	1865
2010-01-01	1222
2010-04-01	2122
2010-07-01	2872
2010-10-01	2172
2011-01-01	2500
2011-04-01	2222
2011-07-01	2504
2011-10-01	2476
2012-01-01	2972
2012-04-01	3205
2012-07-01	2182
2012-10-01	2182
2013-01-01	957
2013-04-01	2839
2013-07-01	4032
2013-10-01	4032
2014-01-01	5753
2014-04-01	4221
2014-07-01	3471
2014-10-01	3471
2015-01-01	2500
2015-04-01	2250
2015-07-01	1750
2015-10-01	2250
2016-01-01	3000
2016-04-01	2000
2016-07-01	2300
2016-10-01	7195
2017-01-01	6396
2017-04-01	7333
2017-07-01	7035
2017-10-01	5056
2018-01-01	4387
2018-04-01	4539