Quarter	Millions of US Dollars
1972-04-01	11
1975-10-01	18
1976-07-01	367
1976-10-01	11
1977-01-01	25
1979-01-01	30
1981-07-01	43
1981-10-01	119
1982-01-01	42
1982-10-01	100
1983-07-01	110
1983-10-01	64
1984-01-01	-4
1984-04-01	51
1984-07-01	66
1985-01-01	490
1985-04-01	180
1985-07-01	21
1985-10-01	186
1986-01-01	147
1986-04-01	159
1986-07-01	20
1986-10-01	100
1987-01-01	86
1987-04-01	51
1987-07-01	192
1987-10-01	32
1988-01-01	-12
1988-04-01	109
1988-07-01	174
1988-10-01	78
1989-01-01	-32
1989-04-01	105
1989-07-01	-106
1989-10-01	250
1990-01-01	375
1990-07-01	219
1990-10-01	348
1991-01-01	50
1991-04-01	543
1991-07-01	107
1991-10-01	585
1992-01-01	-48
1992-04-01	130
1992-07-01	726
1992-10-01	703
1993-01-01	57
1993-04-01	564
1993-07-01	1170
1993-10-01	4064
1994-01-01	1174
1994-04-01	2626
1994-07-01	2072
1994-10-01	1139
1995-01-01	-496
1995-04-01	999
1995-07-01	2894
1995-10-01	595
1996-01-01	1944
1996-04-01	2940
1996-07-01	2095
1996-10-01	4868
1997-01-01	2880
1997-04-01	4100
1997-07-01	3366
1997-10-01	1520
1998-01-01	216
1998-04-01	897
1998-07-01	-915
1998-10-01	-589
1999-01-01	17
1999-04-01	7
1999-07-01	-705
1999-10-01	-846
2000-01-01	1341
2000-04-01	-671
2000-07-01	129
2000-10-01	-592
2001-01-01	-93
2001-04-01	1576
2001-07-01	142
2001-10-01	662
2002-01-01	1731
2002-04-01	2229
2002-07-01	-72
2002-10-01	-110
2003-01-01	979
2003-04-01	1246
2003-07-01	1631
2003-10-01	-524
2004-01-01	2122
2004-04-01	2956
2004-07-01	941
2004-10-01	1037
2005-01-01	64
2005-04-01	1660
2005-07-01	2317
2005-10-01	1398
2006-01-01	946
2006-04-01	1380
2006-07-01	1477
2006-10-01	1296
2007-01-01	331
2007-04-01	4755
2007-07-01	-328
2007-10-01	1914
2008-01-01	-542
2008-04-01	-822
2008-07-01	-1009
2008-10-01	-2136
2009-01-01	-905
2009-04-01	1535
2009-07-01	2171
2009-10-01	5541
2010-01-01	-117
2010-04-01	270
2010-07-01	701
2010-10-01	6768
2011-01-01	-59
2011-04-01	5964
2011-07-01	2423
2011-10-01	393
2012-01-01	1755
2012-04-01	2338
2012-07-01	2410
2012-10-01	3462
2013-01-01	6797
2013-04-01	6675
2013-07-01	4296
2013-10-01	6981
2014-01-01	3331
2014-04-01	4716
2014-07-01	3861
2014-10-01	4649
2015-01-01	430
2015-04-01	5884
2015-07-01	-839
2015-10-01	-3908
2016-01-01	1082
2016-04-01	2451
2016-07-01	4260
2016-10-01	1358
2017-01-01	6576
2017-04-01	7002
2017-07-01	3819
2017-10-01	4704
2018-01-01	4377
2018-04-01	6446