Quarter	US dollars
1999-03-31	20
1999-06-30	14
1999-09-30	13
1999-12-31	16
2000-03-31	11
2000-06-30	19
2000-09-30	6
2000-12-31	4
2001-03-31	1
2001-06-30	1
2001-09-30	1
2001-12-31	3
2002-03-31	4
2002-06-30	4
2002-09-30	1
2002-12-31	3
2003-03-31	2
2003-06-30	1
2003-09-30	1
2003-12-31	3
2004-03-31	1
2004-06-30	1
2004-09-30	1
2004-12-31	1
2005-03-31	1
2005-06-30	1
2005-09-30	1
2005-12-31	1
2006-03-31	1
2006-06-30	1
2006-09-30	1
2006-12-31	1
2007-03-31	2
2007-06-30	2
2007-09-30	2
2007-12-31	1
2008-03-31	1
2008-06-30	5
2008-09-30	10
2008-12-31	11
2009-03-31	13
2009-06-30	11
2009-09-30	11
2009-12-31	11
2010-03-31	10
2010-06-30	9
2010-09-30	10
2010-12-31	9
2011-03-31	8
2011-06-30	6
2011-09-30	6
2011-12-31	25
2012-03-31	30
2012-06-30	31
2012-09-30	4
2012-12-31	4
2013-03-31	371
2013-06-30	349
2013-09-30	297
2013-12-31	453
2014-03-31	442
2014-06-30	882
2014-09-30	882
2014-12-31	831
2015-03-31	800
2015-06-30	775
2015-09-30	644
2015-12-31	713
2016-03-31	751
2016-06-30	715
2016-09-30	711
2016-12-31	647
2017-03-31	723
2017-06-30	763
2017-09-30	794
2017-12-31	803
2018-03-31	1184
2018-06-30	1322
2018-09-30	1323
2018-12-31	1346
2019-03-31	1357
2019-06-30	1346
2019-09-30	1352
2019-12-31	1404
2020-03-31	1439
2020-06-30	1442
2020-09-30	1463
2020-12-31	1496
2021-03-31	1540
2021-06-30	1206
2021-09-30	1232
2021-12-31	1266
2022-03-31	453
2022-06-30	477
2022-09-30	480
2022-12-31	471
2023-03-31	457
2023-06-30	477
2023-09-30	201