Quarter	US dollars
1999-03-31	2959
1999-06-30	3164
1999-09-30	4172
1999-12-31	3281
2000-03-31	2932
2000-06-30	3612
2000-09-30	4027
2000-12-31	4325
2001-03-31	3223
2001-06-30	3455
2001-09-30	2776
2001-12-31	3115
2002-03-31	3703
2002-06-30	4446
2002-09-30	4239
2002-12-31	4751
2003-03-31	5001
2003-06-30	4262
2003-09-30	3298
2003-12-31	5196
2004-03-31	6266
2004-06-30	4098
2004-09-30	4347
2004-12-31	4176
2005-03-31	4449
2005-06-30	3267
2005-09-30	5237
2005-12-31	4901
2006-03-31	4962
2006-06-30	4320
2006-09-30	3771
2006-12-31	4661
2007-03-31	4584
2007-06-30	6274
2007-09-30	6679
2007-12-31	10371
2008-03-31	11864
2008-06-30	9175
2008-09-30	10499
2008-12-31	7611
2009-03-31	9452
2009-06-30	8568
2009-09-30	8560
2009-12-31	8285
2010-03-31	8550
2010-06-30	9806
2010-09-30	9027
2010-12-31	10617
2011-03-31	9569
2011-06-30	9582
2011-09-30	7573
2011-12-31	8865
2012-03-31	8451
2012-06-30	8917
2012-09-30	7741
2012-12-31	7133
2013-03-31	5523
2013-06-30	4819
2013-09-30	6072
2013-12-31	5230
2014-03-31	8826
2014-06-30	7379
2014-09-30	8894
2014-12-31	9215
2015-03-31	10365
2015-06-30	10495
2015-09-30	12676
2015-12-31	8096
2016-03-31	10275
2016-06-30	10318
2016-09-30	11348
2016-12-31	8720
2017-03-31	7539
2017-06-30	6588
2017-09-30	11758
2017-12-31	11263
2018-03-31	12359
2018-06-30	11143
2018-09-30	9108
2018-12-31	9668
2019-03-31	9063
2019-06-30	7788
2019-09-30	7539
2019-12-31	6746
2020-03-31	6458
2020-06-30	5932
2020-09-30	6356
2020-12-31	7888
2021-03-31	6730
2021-06-30	5888
2021-09-30	6267
2021-12-31	6407
2022-03-31	6201
2022-06-30	6430
2022-09-30	5284
2022-12-31	4891
2023-03-31	5054
2023-06-30	5284
2023-09-30	6203