Quarter	US dollars
1999-03-31	4419
1999-06-30	4729
1999-09-30	5528
1999-12-31	4459
2000-03-31	7019
2000-06-30	4255
2000-09-30	4355
2000-12-31	4298
2001-03-31	7253
2001-06-30	4987
2001-09-30	6166
2001-12-31	6333
2002-03-31	6233
2002-06-30	7067
2002-09-30	8819
2002-12-31	8717
2003-03-31	8567
2003-06-30	12433
2003-09-30	13383
2003-12-31	11332
2004-03-31	17249
2004-06-30	15654
2004-09-30	17347
2004-12-31	15845
2005-03-31	17007
2005-06-30	17714
2005-09-30	17003
2005-12-31	16268
2006-03-31	16642
2006-06-30	23063
2006-09-30	21663
2006-12-31	23017
2007-03-31	32786
2007-06-30	30127
2007-09-30	27201
2007-12-31	23407
2008-03-31	24807
2008-06-30	32659
2008-09-30	30034
2008-12-31	27702
2009-03-31	33040
2009-06-30	39542
2009-09-30	35049
2009-12-31	27726
2010-03-31	32736
2010-06-30	29498
2010-09-30	39614
2010-12-31	40697
2011-03-31	36785
2011-06-30	50065
2011-09-30	54740
2011-12-31	48947
2012-03-31	58286
2012-06-30	63125
2012-09-30	65995
2012-12-31	62687
2013-03-31	53852
2013-06-30	42881
2013-09-30	44231
2013-12-31	45059
2014-03-31	51762
2014-06-30	50016
2014-09-30	51034
2014-12-31	48936
2015-03-31	45432
2015-06-30	48335
2015-09-30	51448
2015-12-31	56807
2016-03-31	49126
2016-06-30	52752
2016-09-30	48358
2016-12-31	56957
2017-03-31	51528
2017-06-30	43716
2017-09-30	39804
2017-12-31	43062
2018-03-31	51353
2018-06-30	50870
2018-09-30	52823
2018-12-31	55392
2019-03-31	42608
2019-06-30	40590
2019-09-30	43030
2019-12-31	42252
2020-03-31	53857
2020-06-30	58022
2020-09-30	55833
2020-12-31	66123
2021-03-31	52571
2021-06-30	43628
2021-09-30	39012
2021-12-31	47682
2022-03-31	41510
2022-06-30	45136
2022-09-30	50084
2022-12-31	53615
2023-03-31	39175
2023-06-30	35060
2023-09-30	38184