Quarter	US dollars
1986-12-31	16176
1987-03-31	10358
1987-06-30	-133
1987-09-30	449
1987-12-31	7630
1988-03-31	113
1988-06-30	4761
1988-09-30	-732
1988-12-31	5248
1989-03-31	670
1989-06-30	-6241
1989-09-30	20052
1989-12-31	-369
1990-03-31	18884
1990-06-30	9963
1990-09-30	4947
1990-12-31	-16839
1991-03-31	29799
1991-06-30	16701
1991-09-30	-9125
1991-12-31	-18176
1992-03-31	9572
1992-06-30	1001
1992-09-30	3659
1992-12-31	-61412
1993-03-31	3344
1993-06-30	10575
1993-09-30	10507
1993-12-31	3493
1994-03-31	10261
1994-06-30	7909
1994-09-30	4912
1994-12-31	10375
1995-03-31	8598
1995-06-30	-607
1995-09-30	-3874
1995-12-31	4044
1996-03-31	11778
1996-06-30	3853
1996-09-30	9161
1996-12-31	9109
1997-03-31	18111
1997-06-30	12653
1997-09-30	-78615
1997-12-31	-29042
1998-03-31	1639
1998-06-30	28948
1998-09-30	10213
1998-12-31	-21367
1999-03-31	151265
1999-06-30	47966
1999-09-30	-68719
1999-12-31	-27264
2000-03-31	35101
2000-06-30	22355
2000-09-30	6588
2000-12-31	-8366
2001-03-31	35072
2001-06-30	-5073
2001-09-30	2285
2001-12-31	14548
2002-03-31	9062
2002-06-30	-12725
2002-09-30	14844
2002-12-31	21440
2003-03-31	-3168
2003-06-30	1090
2003-09-30	36572
2003-12-31	-564
2004-03-31	46012
2004-06-30	23489
2004-09-30	4606
2004-12-31	-15427
2005-03-31	17286
2005-06-30	22403
2005-09-30	28179
2005-12-31	15362
2006-03-31	52780
2006-06-30	39303
2006-09-30	76721
2006-12-31	-2944
2007-03-31	77170
2007-06-30	54822
2007-09-30	53775
2007-12-31	-18929
2008-03-31	68145
2008-06-30	-56753
2008-09-30	93381
2008-12-31	-25582
2009-03-31	72081
2009-06-30	8053
2009-09-30	65455
2009-12-31	15565
2010-03-31	18515
2010-06-30	-67592
2010-09-30	42276
2010-12-31	-37891
2011-03-31	15329
2011-06-30	-16509
2011-09-30	-58988
2011-12-31	-39027
2012-03-31	8350
2012-06-30	-13585
2012-09-30	-35926
2012-12-31	-17116
2013-03-31	4112
2013-06-30	-55727
2013-09-30	-37425
2013-12-31	-31739
2014-03-31	11055
2014-06-30	-1787
2014-09-30	31644
2014-12-31	-7245
2015-03-31	30961
2015-06-30	-23916
2015-09-30	28075
2015-12-31	-21332
2016-03-31	19987
2016-06-30	65006
2016-09-30	42033
2016-12-31	-5161
2017-03-31	12139
2017-06-30	-4862
2017-09-30	1629
2017-12-31	-923
2018-03-31	16906
2018-06-30	20835
2018-09-30	7762
2018-12-31	28232
2019-03-31	-34860
2019-06-30	42971
2019-09-30	50823
2019-12-31	-65109