Quarter	US dollars
1999-03-31	2495
1999-06-30	-293
1999-09-30	-743
1999-12-31	-551
2000-03-31	-1872
2000-06-30	234
2000-09-30	-344
2000-12-31	1419
2001-03-31	-759
2001-06-30	-165
2001-09-30	-289
2001-12-31	-1230
2002-03-31	42
2002-06-30	2578
2002-09-30	-1388
2002-12-31	1613
2003-03-31	1244
2003-06-30	-1104
2003-09-30	1420
2003-12-31	1638
2004-03-31	1856
2004-06-30	-132
2004-09-30	3658
2004-12-31	4063
2005-03-31	-1955
2005-06-30	2140
2005-09-30	1650
2005-12-31	6216
2006-03-31	6918
2006-06-30	-2032
2006-09-30	5355
2006-12-31	5136
2007-03-31	605
2007-06-30	13008
2007-09-30	6437
2007-12-31	21775
2008-03-31	7945
2008-06-30	-686
2008-09-30	5365
2008-12-31	2424
2009-03-31	-7893
2009-06-30	-2715
2009-09-30	-2536
2009-12-31	-2525
2010-03-31	3494
2010-06-30	5578
2010-09-30	-3519
2010-12-31	5537
2011-03-31	1
2011-06-30	-1438
2011-09-30	-4704
2011-12-31	4508
2012-03-31	3297
2012-06-30	-2904
2012-09-30	6975
2012-12-31	2331
2013-03-31	-7129
2013-06-30	-4677
2013-09-30	6083
2013-12-31	-9838
2014-03-31	18304
2014-06-30	-5518
2014-09-30	8571
2014-12-31	5144
2015-03-31	2103
2015-06-30	7772
2015-09-30	2629
2015-12-31	12610
2016-03-31	-10023
2016-06-30	6604
2016-09-30	3769
2016-12-31	189
2017-03-31	2101
2017-06-30	-4401
2017-09-30	4408
2017-12-31	13533
2018-03-31	15612
2018-06-30	-7992
2018-09-30	-1172
2018-12-31	5753
2019-03-31	14118
2019-06-30	8823
2019-09-30	-2081
2019-12-31	12379
2020-03-31	-7867
2020-06-30	-6946
2020-09-30	2999
2020-12-31	12001
2021-03-31	317
2021-06-30	-2186
2021-09-30	-5571
2021-12-31	9641
2022-03-31	-580
2022-06-30	-193
2022-09-30	-755
2022-12-31	-3549
2023-03-31	-7909
2023-06-30	2061
2023-09-30	-2369