Quarter	US dollars
1999-03-31	7380
1999-06-30	6599
1999-09-30	7096
1999-12-31	8511
2000-03-31	7773
2000-06-30	8750
2000-09-30	8090
2000-12-31	10494
2001-03-31	10335
2001-06-30	11056
2001-09-30	11637
2001-12-31	14314
2002-03-31	12862
2002-06-30	14849
2002-09-30	13571
2002-12-31	15792
2003-03-31	15950
2003-06-30	19090
2003-09-30	20960
2003-12-31	23187
2004-03-31	22832
2004-06-30	22445
2004-09-30	20195
2004-12-31	22005
2005-03-31	18372
2005-06-30	19377
2005-09-30	17565
2005-12-31	17560
2006-03-31	19111
2006-06-30	20723
2006-09-30	23624
2006-12-31	23213
2007-03-31	19462
2007-06-30	22097
2007-09-30	22472
2007-12-31	23616
2008-03-31	26710
2008-06-30	30616
2008-09-30	24751
2008-12-31	19926
2009-03-31	19690
2009-06-30	19289
2009-09-30	23213
2009-12-31	34077
2010-03-31	35891
2010-06-30	31513
2010-09-30	36547
2010-12-31	31732
2011-03-31	36948
2011-06-30	39491
2011-09-30	37603
2011-12-31	34116
2012-03-31	36870
2012-06-30	37193
2012-09-30	35558
2012-12-31	35496
2013-03-31	34476
2013-06-30	34972
2013-09-30	20846
2013-12-31	23183
2014-03-31	23000
2014-06-30	22502
2014-09-30	20063
2014-12-31	20014
2015-03-31	17417
2015-06-30	17816
2015-09-30	10801
2015-12-31	10061
2016-03-31	9406
2016-06-30	9382
2016-09-30	9035
2016-12-31	7825
2017-03-31	8046
2017-06-30	8842
2017-09-30	7850
2017-12-31	6161
2018-03-31	6041
2018-06-30	5249
2018-09-30	4308
2018-12-31	3380
2019-03-31	2138
2019-06-30	2052
2019-09-30	1787
2019-12-31	1209
2020-03-31	1127
2020-06-30	929
2020-09-30	781
2020-12-31	626
2021-03-31	361
2021-06-30	381
2021-09-30	248
2021-12-31	714
2022-03-31	547
2022-06-30	612
2022-09-30	338
2022-12-31	705
2023-03-31	377
2023-06-30	367
2023-09-30	152