Quarter	US dollars
1999-03-31	5291
1999-06-30	5661
1999-09-30	5587
1999-12-31	2682
2000-03-31	4739
2000-06-30	4162
2000-09-30	2836
2000-12-31	2566
2001-03-31	2507
2001-06-30	3602
2001-09-30	2779
2001-12-31	1896
2002-03-31	2446
2002-06-30	2057
2002-09-30	4577
2002-12-31	1654
2003-03-31	5800
2003-06-30	3069
2003-09-30	4578
2003-12-31	2207
2004-03-31	4103
2004-06-30	3049
2004-09-30	2853
2004-12-31	3902
2005-03-31	8233
2005-06-30	3868
2005-09-30	9118
2005-12-31	1987
2006-03-31	8480
2006-06-30	6088
2006-09-30	10149
2006-12-31	4289
2007-03-31	11729
2007-06-30	7905
2007-09-30	17716
2007-12-31	9745
2008-03-31	23992
2008-06-30	11904
2008-09-30	7223
2008-12-31	3931
2009-03-31	4207
2009-06-30	4469
2009-09-30	8511
2009-12-31	12049
2010-03-31	14314
2010-06-30	12463
2010-09-30	12066
2010-12-31	12032
2011-03-31	15899
2011-06-30	17643
2011-09-30	17400
2011-12-31	16014
2012-03-31	18696
2012-06-30	14135
2012-09-30	15392
2012-12-31	15394
2013-03-31	30495
2013-06-30	37227
2013-09-30	34776
2013-12-31	35788
2014-03-31	47754
2014-06-30	44795
2014-09-30	40485
2014-12-31	29203
2015-03-31	33956
2015-06-30	35813
2015-09-30	30839
2015-12-31	28021
2016-03-31	27520
2016-06-30	28344
2016-09-30	25850
2016-12-31	30881
2017-03-31	33320
2017-06-30	36444
2017-09-30	43564
2017-12-31	47965
2018-03-31	40919
2018-06-30	35395
2018-09-30	46534
2018-12-31	48650
2019-03-31	52936
2019-06-30	49806
2019-09-30	41300
2019-12-31	44881
2020-03-31	46449
2020-06-30	38496
2020-09-30	35895
2020-12-31	42279
2021-03-31	43955
2021-06-30	43625
2021-09-30	45274
2021-12-31	46501
2022-03-31	38624
2022-06-30	39608
2022-09-30	41663
2022-12-31	43808
2023-03-31	43802
2023-06-30	38475
2023-09-30	42139