Quarter	Millions of US Dollars
1989-04-01	353
1989-07-01	204
1989-10-01	126
1990-01-01	164
1990-04-01	187
1990-07-01	65
1990-10-01	218
1991-01-01	944
1991-04-01	107
1991-07-01	202
1991-10-01	173
1992-01-01	393
1992-04-01	278
1992-07-01	735
1992-10-01	152
1993-01-01	49
1993-04-01	258
1993-07-01	265
1993-10-01	516
1994-01-01	38
1994-04-01	39
1994-07-01	256
1994-10-01	110
1995-01-01	821
1995-04-01	665
1995-07-01	-141
1995-10-01	396
1996-01-01	746
1996-04-01	276
1996-07-01	291
1996-10-01	64
1997-01-01	408
1997-04-01	84
1997-07-01	131
1997-10-01	285
1998-01-01	817
1998-04-01	606
1998-07-01	1333
1998-10-01	1302
1999-01-01	1025
1999-04-01	1182
1999-07-01	112
1999-10-01	1622
2000-01-01	602
2000-04-01	1563
2000-07-01	983
2000-10-01	1443
2001-01-01	1913
2001-04-01	681
2001-07-01	1444
2001-10-01	1703
2002-01-01	543
2002-04-01	-783
2002-07-01	1799
2002-10-01	922
2003-01-01	851
2003-04-01	-227
2003-07-01	1621
2003-10-01	648
2004-01-01	1016
2004-04-01	-436
2004-07-01	3556
2004-10-01	1346
2005-01-01	61
2005-04-01	2077
2005-07-01	3372
2005-10-01	-2104
2006-01-01	494
2006-04-01	2841
2006-07-01	1513
2006-10-01	65
2007-01-01	330
2007-04-01	4510
2007-07-01	2423
2007-10-01	904
2008-01-01	3841
2008-04-01	3381
2008-07-01	-4479
2008-10-01	2083
2009-01-01	2368
2009-04-01	5186
2009-07-01	4892
2009-10-01	785
2010-01-01	2072
2010-04-01	1073
2010-07-01	0
2010-10-01	3275
2011-01-01	794
2011-04-01	4231
2011-07-01	-2303
2011-10-01	2308
2012-01-01	4220
2012-04-01	-867
2012-07-01	979
2012-10-01	-1065
2013-01-01	3302
2013-04-01	-7036
2013-07-01	-7883
2013-10-01	-2455
2014-01-01	-12624
2014-04-01	-6971
2014-07-01	783
2014-10-01	-2344
2015-01-01	1384
2015-04-01	3936
2015-07-01	-1689
2015-10-01	1977
2016-01-01	3050
2016-04-01	-445
2016-07-01	-1612
2016-10-01	2076
2017-01-01	4866
2017-04-01	-3342
2017-07-01	3609
2017-10-01	-823
2018-01-01	3737