Quarter	US dollars
1999-03-31	3983
1999-06-30	4472
1999-09-30	4719
1999-12-31	4609
2000-03-31	4660
2000-06-30	4779
2000-09-30	3962
2000-12-31	3710
2001-03-31	3548
2001-06-30	5101
2001-09-30	4180
2001-12-31	3937
2002-03-31	5449
2002-06-30	6773
2002-09-30	5787
2002-12-31	6922
2003-03-31	5862
2003-06-30	5641
2003-09-30	6841
2003-12-31	7553
2004-03-31	7313
2004-06-30	7719
2004-09-30	8383
2004-12-31	8515
2005-03-31	9730
2005-06-30	10678
2005-09-30	11111
2005-12-31	10813
2006-03-31	11489
2006-06-30	13032
2006-09-30	13876
2006-12-31	15356
2007-03-31	16405
2007-06-30	18907
2007-09-30	22525
2007-12-31	20809
2008-03-31	23155
2008-06-30	19253
2008-09-30	17991
2008-12-31	12624
2009-03-31	13806
2009-06-30	14846
2009-09-30	19504
2009-12-31	18736
2010-03-31	20623
2010-06-30	15625
2010-09-30	15718
2010-12-31	12810
2011-03-31	13430
2011-06-30	17363
2011-09-30	17290
2011-12-31	16531
2012-03-31	15065
2012-06-30	14622
2012-09-30	16094
2012-12-31	15806
2013-03-31	16885
2013-06-30	21999
2013-09-30	20463
2013-12-31	21094
2014-03-31	16489
2014-06-30	18926
2014-09-30	18165
2014-12-31	15940
2015-03-31	17033
2015-06-30	17921
2015-09-30	19742
2015-12-31	18942
2016-03-31	20661
2016-06-30	20837
2016-09-30	22201
2016-12-31	17304
2017-03-31	18008
2017-06-30	19905
2017-09-30	18879
2017-12-31	20232
2018-03-31	21942
2018-06-30	24254
2018-09-30	21196
2018-12-31	19560
2019-03-31	24420
2019-06-30	21253
2019-09-30	19965
2019-12-31	22409
2020-03-31	25426
2020-06-30	23146
2020-09-30	29377
2020-12-31	33542
2021-03-31	32395
2021-06-30	31945
2021-09-30	27035
2021-12-31	28300
2022-03-31	31220
2022-06-30	31471
2022-09-30	26820
2022-12-31	26560
2023-03-31	26224
2023-06-30	26309
2023-09-30	24259