Quarter	Millions of US Dollars
1987-04-01	46
1987-07-01	20
1987-10-01	98
1988-01-01	46
1988-04-01	71
1988-07-01	100
1988-10-01	50
1989-01-01	70
1989-04-01	100
1989-07-01	105
1989-10-01	102
1990-01-01	152
1990-04-01	109
1990-07-01	162
1990-10-01	20
1991-01-01	123
1991-04-01	146
1991-07-01	230
1991-10-01	24
1992-01-01	297
1992-04-01	74
1992-07-01	230
1992-10-01	-74
1993-01-01	242
1993-04-01	77
1993-07-01	240
1993-10-01	16
1994-01-01	119
1994-04-01	83
1994-07-01	198
1994-10-01	15
1995-01-01	140
1995-04-01	103
1995-07-01	262
1995-10-01	-25
1996-01-01	311
1996-04-01	130
1996-07-01	129
1996-10-01	75
1997-01-01	202
1997-04-01	230
1997-07-01	224
1997-10-01	-59
1998-01-01	268
1998-04-01	138
1998-07-01	289
1998-10-01	10
1999-01-01	142
1999-04-01	157
1999-07-01	216
1999-10-01	91
2000-01-01	-17
2000-04-01	113
2000-07-01	60
2000-10-01	149
2001-01-01	-171
2001-04-01	261
2001-07-01	218
2001-10-01	288
2002-01-01	339
2002-04-01	239
2002-07-01	215
2002-10-01	163
2003-01-01	526
2003-04-01	174
2003-07-01	630
2003-10-01	412
2004-01-01	288
2004-04-01	499
2004-07-01	315
2004-10-01	850
2005-01-01	186
2005-04-01	839
2005-07-01	931
2005-10-01	807
2006-01-01	302
2006-04-01	1292
2006-07-01	451
2006-10-01	1596
2007-01-01	-176
2007-04-01	1667
2007-07-01	1256
2007-10-01	1779
2008-01-01	-1233
2008-04-01	3196
2008-07-01	732
2008-10-01	-2560
2009-01-01	96
2009-04-01	-367
2009-07-01	224
2009-10-01	295
2010-01-01	-534
2010-04-01	2079
2010-07-01	550
2010-10-01	49
2011-01-01	486
2011-04-01	194
2011-07-01	-127
2011-10-01	1536
2012-01-01	179
2012-04-01	182
2012-07-01	-155
2012-10-01	131
2013-01-01	518
2013-04-01	-154
2013-07-01	21
2013-10-01	137
2014-01-01	-235
2014-04-01	-75
2014-07-01	265
2014-10-01	474
2015-01-01	85
2015-04-01	62
2015-07-01	563
2015-10-01	23
2016-01-01	375
2016-04-01	-117
2016-07-01	421
2016-10-01	-146
2017-01-01	-35
2017-04-01	441
2017-07-01	-123
2017-10-01	-298
2018-01-01	278