Quarter	Millions of US Dollars
1972-04-01	32
1972-10-01	20
1973-10-01	30
1975-04-01	12
1975-10-01	19
1976-04-01	25
1976-07-01	60
1976-10-01	71
1977-01-01	62
1977-07-01	30
1977-10-01	62
1978-01-01	25
1979-01-01	25
1981-01-01	75
1981-07-01	-30
1981-10-01	-25
1982-04-01	-4
1982-07-01	58
1982-10-01	-20
1983-01-01	-67
1983-04-01	-25
1983-10-01	58
1984-07-01	-15
1985-01-01	4
1985-04-01	-25
1985-10-01	42
1986-01-01	-86
1986-04-01	36
1986-10-01	155
1987-01-01	50
1987-04-01	102
1987-10-01	73
1988-04-01	80
1988-07-01	153
1988-10-01	107
1989-01-01	69
1989-04-01	184
1989-07-01	464
1989-10-01	-183
1990-01-01	137
1990-04-01	-91
1990-10-01	-65
1991-01-01	-30
1991-04-01	-67
1991-07-01	-55
1991-10-01	-66
1992-01-01	-68
1992-04-01	-88
1992-10-01	-75
1993-01-01	-103
1993-04-01	-40
1993-07-01	150
1993-10-01	-60
1994-01-01	88
1994-04-01	-23
1994-07-01	-237
1994-10-01	100
1995-01-01	-25
1995-04-01	0
1995-07-01	40
1995-10-01	-120
1996-01-01	9
1996-04-01	502
1996-07-01	-213
1996-10-01	212
1997-01-01	156
1997-04-01	208
1997-07-01	960
1997-10-01	94
1998-01-01	33
1998-04-01	1506
1998-07-01	164
1998-10-01	-39
1999-01-01	913
1999-04-01	297
1999-07-01	703
1999-10-01	312
2000-01-01	-119
2000-04-01	1623
2000-07-01	393
2000-10-01	31
2001-01-01	-149
2001-04-01	985
2001-07-01	2051
2001-10-01	3917
2002-01-01	359
2002-04-01	8
2002-07-01	42
2002-10-01	214
2003-01-01	303
2003-04-01	994
2003-07-01	1230
2003-10-01	3349
2004-01-01	366
2004-04-01	2066
2004-07-01	2990
2004-10-01	3652
2005-01-01	3348
2005-04-01	-712
2005-07-01	2775
2005-10-01	1603
2006-01-01	173
2006-04-01	3925
2006-07-01	1654
2006-10-01	1002
2007-01-01	2278
2007-04-01	5354
2007-07-01	-429
2007-10-01	-315
2008-01-01	-201
2008-04-01	-633
2008-07-01	1311
2008-10-01	-2750
2009-01-01	-2476
2009-04-01	-2525
2009-07-01	1089
2009-10-01	1721
2010-01-01	703
2010-04-01	-141
2010-07-01	3300
2010-10-01	157
2011-01-01	3755
2011-04-01	3043
2011-07-01	1287
2011-10-01	1263
2012-01-01	9415
2012-04-01	-1563
2012-07-01	6870
2012-10-01	4185
2013-01-01	5003
2013-04-01	6400
2013-07-01	8348
2013-10-01	2356
2014-01-01	3026
2014-04-01	4386
2014-07-01	8879
2014-10-01	-5053
2015-01-01	-2255
2015-04-01	5933
2015-07-01	-2425
2015-10-01	-2295
2016-01-01	2250
2016-04-01	3722
2016-07-01	4669
2016-10-01	-1764
2017-01-01	6310
2017-04-01	9298
2017-07-01	7414
2017-10-01	1926
2018-01-01	10874
2018-04-01	14734