Quarter	US dollars
1999-03-31	5745
1999-06-30	5344
1999-09-30	5654
1999-12-31	5641
2000-03-31	5461
2000-06-30	5814
2000-09-30	3121
2000-12-31	2456
2001-03-31	2339
2001-06-30	3830
2001-09-30	4987
2001-12-31	5249
2002-03-31	5357
2002-06-30	5040
2002-09-30	5434
2002-12-31	4947
2003-03-31	6336
2003-06-30	4854
2003-09-30	6773
2003-12-31	6458
2004-03-31	5969
2004-06-30	6680
2004-09-30	5081
2004-12-31	5573
2005-03-31	7722
2005-06-30	6738
2005-09-30	6244
2005-12-31	6615
2006-03-31	10428
2006-06-30	11394
2006-09-30	11959
2006-12-31	9930
2007-03-31	12724
2007-06-30	13663
2007-09-30	13314
2007-12-31	15406
2008-03-31	13773
2008-06-30	18034
2008-09-30	16461
2008-12-31	14149
2009-03-31	11979
2009-06-30	13627
2009-09-30	13448
2009-12-31	16736
2010-03-31	15908
2010-06-30	16814
2010-09-30	13848
2010-12-31	18056
2011-03-31	16757
2011-06-30	18422
2011-09-30	19437
2011-12-31	14938
2012-03-31	18551
2012-06-30	17604
2012-09-30	19901
2012-12-31	16709
2013-03-31	20250
2013-06-30	20117
2013-09-30	21811
2013-12-31	19366
2014-03-31	19408
2014-06-30	18809
2014-09-30	12513
2014-12-31	13965
2015-03-31	13240
2015-06-30	12785
2015-09-30	10829
2015-12-31	12964
2016-03-31	11188
2016-06-30	19838
2016-09-30	22970
2016-12-31	23143
2017-03-31	24018
2017-06-30	25830
2017-09-30	27993
2017-12-31	34505
2018-03-31	38982
2018-06-30	36846
2018-09-30	39680
2018-12-31	34973
2019-03-31	32332
2019-06-30	29052
2019-09-30	30319
2019-12-31	30037
2020-03-31	35169
2020-06-30	35466
2020-09-30	33703
2020-12-31	43176
2021-03-31	41844
2021-06-30	47091
2021-09-30	43494
2021-12-31	49298
2022-03-31	39377
2022-06-30	36599
2022-09-30	31982
2022-12-31	28537
2023-03-31	30586
2023-06-30	29016
2023-09-30	26352