Quarter	US dollars
1999-03-31	7
1999-06-30	6
1999-09-30	7
1999-12-31	4
2000-03-31	3
2000-06-30	10
2000-09-30	4
2000-12-31	7
2001-03-31	5
2001-06-30	6
2001-09-30	9
2001-12-31	9
2002-03-31	9
2002-06-30	13
2002-09-30	10
2002-12-31	9
2003-03-31	3
2003-06-30	20
2003-09-30	12
2003-12-31	12
2004-03-31	17
2004-06-30	7
2004-09-30	6
2004-12-31	2
2005-03-31	2
2005-06-30	3
2005-09-30	2
2005-12-31	2
2006-03-31	4
2006-06-30	4
2006-09-30	2
2006-12-31	14
2007-03-31	23
2007-06-30	74
2007-09-30	79
2007-12-31	98
2008-03-31	79
2008-06-30	78
2008-09-30	199
2008-12-31	89
2009-03-31	57
2009-06-30	92
2009-09-30	72
2009-12-31	90
2010-03-31	58
2010-06-30	117
2010-09-30	131
2010-12-31	91
2011-03-31	72
2011-06-30	86
2011-09-30	84
2011-12-31	147
2012-03-31	183
2012-06-30	187
2012-09-30	190
2012-12-31	103
2013-03-31	134
2013-06-30	127
2013-09-30	135
2013-12-31	167
2014-03-31	197
2014-06-30	234
2014-09-30	226
2014-12-31	198
2015-03-31	165
2015-06-30	160
2015-09-30	144
2015-12-31	152
2016-03-31	160
2016-06-30	176
2016-09-30	155
2016-12-31	148
2017-03-31	158
2017-06-30	163
2017-09-30	80
2017-12-31	41
2018-03-31	54
2018-06-30	56
2018-09-30	50
2018-12-31	69
2019-03-31	58
2019-06-30	116
2019-09-30	96
2019-12-31	64
2020-03-31	65
2020-06-30	55
2020-09-30	89
2020-12-31	112
2021-03-31	124
2021-06-30	119
2021-09-30	125
2021-12-31	97
2022-03-31	142
2022-06-30	36
2022-09-30	26
2022-12-31	24
2023-03-31	25
2023-06-30	26
2023-09-30	-20