Quarter	US dollars
1999-03-31	6692
1999-06-30	5707
1999-09-30	7790
1999-12-31	5547
2000-03-31	6779
2000-06-30	7807
2000-09-30	7007
2000-12-31	7320
2001-03-31	6958
2001-06-30	8932
2001-09-30	11561
2001-12-31	10684
2002-03-31	9702
2002-06-30	11053
2002-09-30	11572
2002-12-31	11312
2003-03-31	10885
2003-06-30	10638
2003-09-30	7563
2003-12-31	8434
2004-03-31	8875
2004-06-30	10092
2004-09-30	10538
2004-12-31	13256
2005-03-31	11029
2005-06-30	8876
2005-09-30	7552
2005-12-31	9569
2006-03-31	10028
2006-06-30	10407
2006-09-30	11194
2006-12-31	11610
2007-03-31	14456
2007-06-30	14884
2007-09-30	12999
2007-12-31	16204
2008-03-31	13654
2008-06-30	15106
2008-09-30	10699
2008-12-31	12814
2009-03-31	7883
2009-06-30	8418
2009-09-30	7598
2009-12-31	4793
2010-03-31	7201
2010-06-30	5687
2010-09-30	6350
2010-12-31	7104
2011-03-31	8836
2011-06-30	5958
2011-09-30	5705
2011-12-31	6488
2012-03-31	6320
2012-06-30	4469
2012-09-30	5438
2012-12-31	3543
2013-03-31	4638
2013-06-30	3889
2013-09-30	4927
2013-12-31	5226
2014-03-31	3932
2014-06-30	4193
2014-09-30	4018
2014-12-31	3501
2015-03-31	2611
2015-06-30	2334
2015-09-30	2668
2015-12-31	2665
2016-03-31	2790
2016-06-30	2725
2016-09-30	2700
2016-12-31	3407
2017-03-31	3581
2017-06-30	3276
2017-09-30	3690
2017-12-31	3404
2018-03-31	4011
2018-06-30	4255
2018-09-30	4381
2018-12-31	2702
2019-03-31	3412
2019-06-30	3515
2019-09-30	4223
2019-12-31	4258
2020-03-31	3256
2020-06-30	2586
2020-09-30	3209
2020-12-31	2598
2021-03-31	3189
2021-06-30	2631
2021-09-30	3171
2021-12-31	3277
2022-03-31	3010
2022-06-30	3498
2022-09-30	3773
2022-12-31	3608
2023-03-31	3646
2023-06-30	4119
2023-09-30	3466