Quarter	US dollars
1999-03-31	19237
1999-06-30	19140
1999-09-30	18433
1999-12-31	15766
2000-03-31	19198
2000-06-30	16582
2000-09-30	15539
2000-12-31	12929
2001-03-31	13237
2001-06-30	15177
2001-09-30	13146
2001-12-31	10295
2002-03-31	15044
2002-06-30	15041
2002-09-30	18302
2002-12-31	15720
2003-03-31	21214
2003-06-30	20074
2003-09-30	24199
2003-12-31	26147
2004-03-31	34888
2004-06-30	34990
2004-09-30	41911
2004-12-31	40945
2005-03-31	50661
2005-06-30	38514
2005-09-30	53024
2005-12-31	37324
2006-03-31	51398
2006-06-30	49386
2006-09-30	59552
2006-12-31	42485
2007-03-31	64660
2007-06-30	69310
2007-09-30	64728
2007-12-31	62764
2008-03-31	87079
2008-06-30	66107
2008-09-30	54634
2008-12-31	38635
2009-03-31	36451
2009-06-30	40976
2009-09-30	44642
2009-12-31	51900
2010-03-31	62017
2010-06-30	65330
2010-09-30	64927
2010-12-31	67522
2011-03-31	84170
2011-06-30	90621
2011-09-30	88494
2011-12-31	79218
2012-03-31	77444
2012-06-30	72973
2012-09-30	72804
2012-12-31	76293
2013-03-31	97598
2013-06-30	108452
2013-09-30	101100
2013-12-31	104864
2014-03-31	119089
2014-06-30	116631
2014-09-30	103774
2014-12-31	89340
2015-03-31	91992
2015-06-30	89430
2015-09-30	77782
2015-12-31	69327
2016-03-31	64858
2016-06-30	63613
2016-09-30	60545
2016-12-31	65537
2017-03-31	70013
2017-06-30	76309
2017-09-30	86015
2017-12-31	91656
2018-03-31	84422
2018-06-30	80587
2018-09-30	90443
2018-12-31	92496
2019-03-31	97864
2019-06-30	92426
2019-09-30	83323
2019-12-31	86841
2020-03-31	90439
2020-06-30	77084
2020-09-30	74053
2020-12-31	81536
2021-03-31	85141
2021-06-30	81150
2021-09-30	83430
2021-12-31	93616
2022-03-31	88271
2022-06-30	89288
2022-09-30	96303
2022-12-31	91432
2023-03-31	89660
2023-06-30	81873
2023-09-30	90228