Quarter	US dollars
1999-03-31	2737
1999-06-30	1747
1999-09-30	1661
1999-12-31	2368
2000-03-31	2748
2000-06-30	3468
2000-09-30	3690
2000-12-31	3461
2001-03-31	4107
2001-06-30	4108
2001-09-30	3886
2001-12-31	4222
2002-03-31	3230
2002-06-30	3287
2002-09-30	2181
2002-12-31	1346
2003-03-31	3418
2003-06-30	2713
2003-09-30	3268
2003-12-31	4571
2004-03-31	4172
2004-06-30	4284
2004-09-30	4727
2004-12-31	4211
2005-03-31	5439
2005-06-30	4154
2005-09-30	4520
2005-12-31	5457
2006-03-31	6501
2006-06-30	6212
2006-09-30	6003
2006-12-31	7079
2007-03-31	5962
2007-06-30	7400
2007-09-30	7425
2007-12-31	9082
2008-03-31	6353
2008-06-30	5681
2008-09-30	5349
2008-12-31	5167
2009-03-31	4231
2009-06-30	5528
2009-09-30	4186
2009-12-31	2815
2010-03-31	2285
2010-06-30	2792
2010-09-30	2494
2010-12-31	2341
2011-03-31	2351
2011-06-30	2698
2011-09-30	3126
2011-12-31	1568
2012-03-31	993
2012-06-30	714
2012-09-30	1462
2012-12-31	1345
2013-03-31	1063
2013-06-30	1200
2013-09-30	1468
2013-12-31	1704
2014-03-31	1663
2014-06-30	1828
2014-09-30	1684
2014-12-31	1937
2015-03-31	1624
2015-06-30	1954
2015-09-30	2140
2015-12-31	2395
2016-03-31	2495
2016-06-30	2294
2016-09-30	2806
2016-12-31	1146
2017-03-31	1058
2017-06-30	1408
2017-09-30	1654
2017-12-31	1485
2018-03-31	1389
2018-06-30	2478
2018-09-30	1831
2018-12-31	2833
2019-03-31	1727
2019-06-30	1859
2019-09-30	2332
2019-12-31	1891
2020-03-31	3324
2020-06-30	2970
2020-09-30	1965
2020-12-31	3262
2021-03-31	2352
2021-06-30	2276
2021-09-30	2590
2021-12-31	1708
2022-03-31	3290
2022-06-30	3241
2022-09-30	2627
2022-12-31	3008
2023-03-31	2618
2023-06-30	3127
2023-09-30	2246