Quarter	US dollars
1999-03-31	12951
1999-06-30	12120
1999-09-30	11478
1999-12-31	10791
2000-03-31	10426
2000-06-30	10984
2000-09-30	12339
2000-12-31	11118
2001-03-31	10722
2001-06-30	10528
2001-09-30	10241
2001-12-31	10925
2002-03-31	11841
2002-06-30	12104
2002-09-30	11538
2002-12-31	11575
2003-03-31	13973
2003-06-30	14040
2003-09-30	14351
2003-12-31	13441
2004-03-31	17251
2004-06-30	15607
2004-09-30	17915
2004-12-31	17945
2005-03-31	16494
2005-06-30	17206
2005-09-30	17015
2005-12-31	17448
2006-03-31	20432
2006-06-30	21173
2006-09-30	23771
2006-12-31	27277
2007-03-31	27465
2007-06-30	31998
2007-09-30	31677
2007-12-31	39226
2008-03-31	39572
2008-06-30	37663
2008-09-30	39517
2008-12-31	34007
2009-03-31	32492
2009-06-30	30592
2009-09-30	31712
2009-12-31	33112
2010-03-31	35182
2010-06-30	38072
2010-09-30	41744
2010-12-31	40166
2011-03-31	41890
2011-06-30	45155
2011-09-30	45402
2011-12-31	44666
2012-03-31	43842
2012-06-30	44525
2012-09-30	42081
2012-12-31	42408
2013-03-31	46337
2013-06-30	45023
2013-09-30	46631
2013-12-31	48097
2014-03-31	50384
2014-06-30	47908
2014-09-30	48321
2014-12-31	45675
2015-03-31	42943
2015-06-30	42658
2015-09-30	46613
2015-12-31	43953
2016-03-31	45813
2016-06-30	46829
2016-09-30	44014
2016-12-31	39735
2017-03-31	40014
2017-06-30	45025
2017-09-30	47079
2017-12-31	47915
2018-03-31	46442
2018-06-30	40689
2018-09-30	42791
2018-12-31	45911
2019-03-31	43310
2019-06-30	44943
2019-09-30	41902
2019-12-31	42582
2020-03-31	47630
2020-06-30	43629
2020-09-30	47343
2020-12-31	48534
2021-03-31	47158
2021-06-30	47773
2021-09-30	50079
2021-12-31	47217
2022-03-31	46363
2022-06-30	46045
2022-09-30	46118
2022-12-31	47422
2023-03-31	46637
2023-06-30	44661
2023-09-30	50475