Quarter	US dollars
1999-03-31	-9938
1999-06-30	-661
1999-09-30	5987
1999-12-31	-3481
2000-03-31	19391
2000-06-30	7609
2000-09-30	17108
2000-12-31	-966
2001-03-31	17207
2001-06-30	7478
2001-09-30	-2029
2001-12-31	-14416
2002-03-31	-14376
2002-06-30	4878
2002-09-30	-3908
2002-12-31	8452
2003-03-31	11588
2003-06-30	-7458
2003-09-30	9823
2003-12-31	17918
2004-03-31	26912
2004-06-30	12169
2004-09-30	29745
2004-12-31	-9133
2005-03-31	31729
2005-06-30	12624
2005-09-30	38098
2005-12-31	7503
2006-03-31	45312
2006-06-30	14878
2006-09-30	46191
2006-12-31	-4832
2007-03-31	37351
2007-06-30	-7140
2007-09-30	53296
2007-12-31	35054
2008-03-31	-44531
2008-06-30	-47818
2008-09-30	40739
2008-12-31	-147866
2009-03-31	-33770
2009-06-30	-5898
2009-09-30	-9126
2009-12-31	-12180
2010-03-31	16127
2010-06-30	5781
2010-09-30	-6546
2010-12-31	12755
2011-03-31	34765
2011-06-30	-8243
2011-09-30	1723
2011-12-31	15754
2012-03-31	35672
2012-06-30	11096
2012-09-30	-16512
2012-12-31	-29704
2013-03-31	32998
2013-06-30	-23990
2013-09-30	14761
2013-12-31	12405
2014-03-31	14284
2014-06-30	13143
2014-09-30	135
2014-12-31	-18006
2015-03-31	-2766
2015-06-30	8893
2015-09-30	17246
2015-12-31	-11766
2016-03-31	-11691
2016-06-30	9942
2016-09-30	180
2016-12-31	-23863
2017-03-31	48415
2017-06-30	-7693
2017-09-30	-7608
2017-12-31	386
2018-03-31	30989
2018-06-30	-43634
2018-09-30	24758
2018-12-31	4920
2019-03-31	51133
2019-06-30	13535
2019-09-30	-22297
2019-12-31	-16800
2020-03-31	56627
2020-06-30	-78832
2020-09-30	-3893
2020-12-31	16060
2021-03-31	22783
2021-06-30	2653
2021-09-30	23771
2021-12-31	2990
2022-03-31	29123
2022-06-30	-6186
2022-09-30	3722
2022-12-31	-38433
2023-03-31	16211
2023-06-30	-6497
2023-09-30	-17627