Quarter	US dollars
1999-09-30	3250
1999-12-31	2990
2000-03-31	3798
2000-06-30	3884
2000-09-30	3685
2000-12-31	3797
2001-03-31	3452
2001-06-30	3767
2001-09-30	3497
2001-12-31	3719
2002-03-31	3841
2002-06-30	4097
2002-09-30	4277
2002-12-31	4194
2003-03-31	4772
2003-06-30	6617
2003-09-30	5685
2003-12-31	5966
2004-03-31	6385
2004-06-30	7039
2004-09-30	7449
2004-12-31	7860
2005-03-31	8613
2005-06-30	9047
2005-09-30	9999
2005-12-31	10161
2006-03-31	11056
2006-06-30	11257
2006-09-30	12554
2006-12-31	13922
2007-03-31	15188
2007-06-30	16563
2007-09-30	18000
2007-12-31	17012
2008-03-31	17597
2008-06-30	19350
2008-09-30	20704
2008-12-31	17603
2009-03-31	16426
2009-06-30	16932
2009-09-30	18194
2009-12-31	19111
2010-03-31	20400
2010-06-30	20365
2010-09-30	20784
2010-12-31	21173
2011-03-31	22052
2011-06-30	22106
2011-09-30	20144
2011-12-31	21039
2012-03-31	21945
2012-06-30	20996
2012-09-30	20012
2012-12-31	19345
2013-03-31	21141
2013-06-30	19793
2013-09-30	19619
2013-12-31	19554
2014-03-31	21200
2014-06-30	21912
2014-09-30	22246
2014-12-31	21550
2015-03-31	21319
2015-06-30	16493
2015-09-30	15966
2015-12-31	15080
2016-03-31	14303
2016-06-30	11949
2016-09-30	12330
2016-12-31	12390
2017-03-31	15291
2017-06-30	11765
2017-09-30	12019
2017-12-31	13787
2018-03-31	9848
2018-06-30	9393
2018-09-30	11188
2018-12-31	11422
2019-03-31	12257
2019-06-30	12820
2019-09-30	12463
2019-12-31	13856
2020-03-31	13198
2020-06-30	12382
2020-09-30	10498
2020-12-31	9695
2021-03-31	10035
2021-06-30	9581
2021-09-30	10384
2021-12-31	9322
2022-03-31	8278
2022-06-30	7790
2022-09-30	6986
2022-12-31	7113
2023-03-31	7090
2023-06-30	7761
2023-09-30	6618