Quarter	US dollars
1999-03-31	1527
1999-06-30	1561
1999-09-30	1537
1999-12-31	1477
2000-03-31	1565
2000-06-30	1448
2000-09-30	1372
2000-12-31	1319
2001-03-31	1229
2001-06-30	1299
2001-09-30	1573
2001-12-31	1702
2002-03-31	1610
2002-06-30	1864
2002-09-30	1828
2002-12-31	2051
2003-03-31	1869
2003-06-30	1786
2003-09-30	1732
2003-12-31	1672
2004-03-31	1864
2004-06-30	1602
2004-09-30	1801
2004-12-31	1821
2005-03-31	1537
2005-06-30	2137
2005-09-30	3118
2005-12-31	3574
2006-03-31	3020
2006-06-30	2701
2006-09-30	2249
2006-12-31	1298
2007-03-31	1121
2007-06-30	1258
2007-09-30	1088
2007-12-31	848
2008-03-31	427
2008-06-30	591
2008-09-30	1170
2008-12-31	923
2009-03-31	786
2009-06-30	672
2009-09-30	1000
2009-12-31	902
2010-03-31	1051
2010-06-30	1002
2010-09-30	1604
2010-12-31	1732
2011-03-31	1716
2011-06-30	1380
2011-09-30	1116
2011-12-31	970
2012-03-31	1131
2012-06-30	986
2012-09-30	1148
2012-12-31	1013
2013-03-31	734
2013-06-30	607
2013-09-30	510
2013-12-31	439
2014-03-31	286
2014-06-30	370
2014-09-30	459
2014-12-31	255
2015-03-31	593
2015-06-30	521
2015-09-30	482
2015-12-31	397
2016-03-31	322
2016-06-30	349
2016-09-30	296
2016-12-31	185
2017-03-31	188
2017-06-30	190
2017-09-30	563
2017-12-31	49
2018-03-31	136
2018-06-30	90
2018-09-30	77
2018-12-31	112
2019-03-31	81
2019-06-30	138
2019-09-30	82
2019-12-31	26
2020-03-31	37
2020-06-30	30
2020-09-30	36
2020-12-31	59
2021-03-31	10
2021-06-30	26
2021-09-30	11
2021-12-31	42
2022-03-31	73
2022-06-30	98
2022-09-30	59
2022-12-31	59
2023-03-31	83
2023-06-30	53
2023-09-30	43