Quarter	US dollars
1999-03-31	20108
1999-06-30	18412
1999-09-30	16693
1999-12-31	17458
2000-03-31	15475
2000-06-30	17754
2000-09-30	19008
2000-12-31	18961
2001-03-31	18480
2001-06-30	16504
2001-09-30	17677
2001-12-31	15602
2002-03-31	12249
2002-06-30	13497
2002-09-30	13486
2002-12-31	14802
2003-03-31	18355
2003-06-30	19582
2003-09-30	19484
2003-12-31	17359
2004-03-31	18550
2004-06-30	20843
2004-09-30	21575
2004-12-31	21210
2005-03-31	17335
2005-06-30	18929
2005-09-30	16551
2005-12-31	14899
2006-03-31	20674
2006-06-30	17711
2006-09-30	22480
2006-12-31	18871
2007-03-31	15525
2007-06-30	21733
2007-09-30	27121
2007-12-31	25207
2008-03-31	34589
2008-06-30	36210
2008-09-30	29289
2008-12-31	23010
2009-03-31	23317
2009-06-30	20161
2009-09-30	23520
2009-12-31	23533
2010-03-31	26313
2010-06-30	31368
2010-09-30	29372
2010-12-31	36834
2011-03-31	36565
2011-06-30	46467
2011-09-30	42962
2011-12-31	37804
2012-03-31	37158
2012-06-30	40818
2012-09-30	32773
2012-12-31	36732
2013-03-31	34983
2013-06-30	33870
2013-09-30	43409
2013-12-31	48306
2014-03-31	55679
2014-06-30	64724
2014-09-30	51782
2014-12-31	51963
2015-03-31	50338
2015-06-30	43351
2015-09-30	34311
2015-12-31	34228
2016-03-31	32465
2016-06-30	33935
2016-09-30	40016
2016-12-31	43896
2017-03-31	40578
2017-06-30	43833
2017-09-30	44906
2017-12-31	41553
2018-03-31	37377
2018-06-30	41981
2018-09-30	41528
2018-12-31	39547
2019-03-31	36157
2019-06-30	35664
2019-09-30	36729
2019-12-31	36315
2020-03-31	45004
2020-06-30	32320
2020-09-30	35417
2020-12-31	37196
2021-03-31	46050
2021-06-30	43686
2021-09-30	47698
2021-12-31	39208
2022-03-31	42932
2022-06-30	44704
2022-09-30	56614
2022-12-31	41447
2023-03-31	50983
2023-06-30	52160
2023-09-30	51790