Quarter	US dollars
1999-03-31	2471
1999-06-30	2219
1999-09-30	2133
1999-12-31	2666
2000-03-31	2703
2000-06-30	2953
2000-09-30	3474
2000-12-31	3684
2001-03-31	4206
2001-06-30	4435
2001-09-30	5161
2001-12-31	4579
2002-03-31	4334
2002-06-30	4879
2002-09-30	4172
2002-12-31	4115
2003-03-31	3696
2003-06-30	3462
2003-09-30	3655
2003-12-31	2670
2004-03-31	2985
2004-06-30	3073
2004-09-30	4430
2004-12-31	6180
2005-03-31	5378
2005-06-30	4831
2005-09-30	5347
2005-12-31	4814
2006-03-31	5933
2006-06-30	5828
2006-09-30	6165
2006-12-31	5962
2007-03-31	12004
2007-06-30	12803
2007-09-30	11546
2007-12-31	9891
2008-03-31	12049
2008-06-30	9763
2008-09-30	9373
2008-12-31	10330
2009-03-31	8545
2009-06-30	6757
2009-09-30	6707
2009-12-31	7221
2010-03-31	8472
2010-06-30	10722
2010-09-30	10334
2010-12-31	8523
2011-03-31	14796
2011-06-30	15251
2011-09-30	11750
2011-12-31	6785
2012-03-31	7276
2012-06-30	9349
2012-09-30	7903
2012-12-31	8876
2013-03-31	10472
2013-06-30	11955
2013-09-30	10501
2013-12-31	11032
2014-03-31	8822
2014-06-30	10898
2014-09-30	9962
2014-12-31	9107
2015-03-31	10188
2015-06-30	8736
2015-09-30	8010
2015-12-31	8474
2016-03-31	9114
2016-06-30	10465
2016-09-30	9128
2016-12-31	8978
2017-03-31	7770
2017-06-30	8262
2017-09-30	9525
2017-12-31	8293
2018-03-31	9244
2018-06-30	9742
2018-09-30	8609
2018-12-31	8985
2019-03-31	8378
2019-06-30	7642
2019-09-30	8005
2019-12-31	8152
2020-03-31	10090
2020-06-30	9653
2020-09-30	8425
2020-12-31	9735
2021-03-31	9341
2021-06-30	9584
2021-09-30	8286
2021-12-31	7002
2022-03-31	6800
2022-06-30	9013
2022-09-30	8766
2022-12-31	7824
2023-03-31	10111
2023-06-30	11649
2023-09-30	12612