Quarter	Millions of US Dollars
1978-01-01	25
1978-04-01	44
1979-01-01	30
1979-04-01	80
1979-07-01	66
1980-04-01	46
1981-07-01	43
1982-01-01	42
1983-01-01	-4
1983-07-01	100
1984-01-01	104
1984-04-01	-80
1984-07-01	42
1985-01-01	400
1985-04-01	40
1985-07-01	21
1985-10-01	295
1986-04-01	-59
1986-07-01	-58
1988-04-01	-80
1988-07-01	248
1989-04-01	-72
1989-07-01	200
1990-01-01	-113
1990-04-01	-300
1990-07-01	-69
1991-01-01	-83
1991-07-01	-170
1991-10-01	-60
1992-01-01	300
1992-07-01	100
1992-10-01	38
1993-01-01	336
1993-04-01	263
1993-07-01	174
1993-10-01	1224
1994-01-01	1564
1994-04-01	140
1994-07-01	519
1994-10-01	296
1995-01-01	190
1995-04-01	268
1995-07-01	535
1995-10-01	437
1996-01-01	1307
1996-04-01	920
1996-07-01	1784
1996-10-01	1045
1997-01-01	689
1997-04-01	1149
1997-07-01	496
1997-10-01	-48
1998-01-01	-363
1998-04-01	70
1998-07-01	-105
1998-10-01	67
1999-01-01	-453
1999-04-01	-60
1999-07-01	-635
1999-10-01	-116
2000-01-01	-291
2000-04-01	230
2000-07-01	-533
2000-10-01	-95
2001-01-01	-706
2001-04-01	-37
2001-07-01	-1175
2001-10-01	-572
2002-01-01	-491
2002-04-01	-332
2002-07-01	962
2002-10-01	-356
2003-01-01	-28
2003-04-01	-154
2003-07-01	-553
2003-10-01	-460
2004-01-01	-1393
2004-04-01	738
2004-07-01	458
2004-10-01	230
2005-01-01	204
2005-04-01	1445
2005-07-01	-493
2005-10-01	229
2006-01-01	-252
2006-04-01	643
2006-07-01	497
2006-10-01	-210
2007-01-01	-662
2007-04-01	-1059
2007-07-01	-50
2007-10-01	-323
2008-01-01	0
2008-04-01	-80
2008-07-01	-30
2008-10-01	-424
2009-01-01	-167
2009-04-01	-450
2009-07-01	-268
2009-10-01	-284
2010-01-01	-250
2010-04-01	-336
2010-07-01	700
2010-10-01	1080
2011-01-01	328
2011-04-01	650
2011-07-01	-218
2011-10-01	387
2012-01-01	1439
2012-04-01	500
2012-07-01	2228
2012-10-01	2128
2013-01-01	1016
2013-04-01	-71
2013-07-01	500
2013-10-01	735
2014-01-01	290
2014-04-01	2750
2014-07-01	-313
2014-10-01	-100
2015-01-01	61
2015-04-01	-601
2015-07-01	-318
2015-10-01	-456
2016-01-01	-100
2016-04-01	674
2016-07-01	840
2016-10-01	-490
2017-01-01	614
2017-04-01	-316
2017-07-01	1991
2017-10-01	-1822
2018-01-01	123
2018-04-01	1347