Quarter	US dollars
1999-03-31	2169
1999-06-30	2628
1999-09-30	3414
1999-12-31	3352
2000-03-31	3164
2000-06-30	4309
2000-09-30	3796
2000-12-31	3397
2001-03-31	5565
2001-06-30	5000
2001-09-30	5301
2001-12-31	7063
2002-03-31	8109
2002-06-30	6921
2002-09-30	9553
2002-12-31	8512
2003-03-31	7916
2003-06-30	10987
2003-09-30	5773
2003-12-31	4637
2004-03-31	4356
2004-06-30	4757
2004-09-30	6532
2004-12-31	5734
2005-03-31	6285
2005-06-30	6079
2005-09-30	6031
2005-12-31	6141
2006-03-31	5964
2006-06-30	6962
2006-09-30	6796
2006-12-31	8131
2007-03-31	6471
2007-06-30	7324
2007-09-30	7376
2007-12-31	9117
2008-03-31	11175
2008-06-30	11766
2008-09-30	10398
2008-12-31	6727
2009-03-31	7199
2009-06-30	9896
2009-09-30	10164
2009-12-31	8575
2010-03-31	8488
2010-06-30	9866
2010-09-30	9235
2010-12-31	8034
2011-03-31	9220
2011-06-30	7284
2011-09-30	14193
2011-12-31	12100
2012-03-31	14452
2012-06-30	15199
2012-09-30	14438
2012-12-31	17314
2013-03-31	14820
2013-06-30	15301
2013-09-30	13901
2013-12-31	14138
2014-03-31	14121
2014-06-30	15864
2014-09-30	13986
2014-12-31	14472
2015-03-31	14760
2015-06-30	13051
2015-09-30	13390
2015-12-31	10383
2016-03-31	10857
2016-06-30	8841
2016-09-30	9219
2016-12-31	7896
2017-03-31	6792
2017-06-30	5483
2017-09-30	4764
2017-12-31	5295
2018-03-31	5755
2018-06-30	5263
2018-09-30	4543
2018-12-31	8237
2019-03-31	8588
2019-06-30	6956
2019-09-30	6084
2019-12-31	4330
2020-03-31	6613
2020-06-30	5309
2020-09-30	6469
2020-12-31	3234
2021-03-31	5478
2021-06-30	5235
2021-09-30	9039
2021-12-31	3440
2022-03-31	6978
2022-06-30	6878
2022-09-30	7671
2022-12-31	4558
2023-03-31	7065
2023-06-30	7782
2023-09-30	7307