Quarter	US dollars
1999-03-31	16
1999-06-30	7
1999-09-30	21
1999-12-31	20
2000-03-31	19
2000-06-30	21
2000-09-30	10
2000-12-31	9
2001-03-31	9
2001-06-30	9
2001-09-30	9
2001-12-31	10
2002-03-31	9
2002-06-30	9
2002-09-30	10
2002-12-31	9
2003-03-31	8
2003-06-30	11
2003-09-30	18
2003-12-31	19
2004-03-31	21
2004-06-30	19
2004-09-30	28
2004-12-31	28
2005-03-31	21
2005-06-30	20
2005-09-30	21
2005-12-31	18
2006-03-31	5
2006-06-30	17
2006-09-30	24
2006-12-31	22
2007-03-31	42
2007-06-30	23
2007-09-30	23
2007-12-31	30
2008-03-31	178
2008-06-30	126
2008-09-30	130
2008-12-31	161
2009-03-31	117
2009-06-30	119
2009-09-30	177
2009-12-31	238
2010-03-31	228
2010-06-30	250
2010-09-30	269
2010-12-31	367
2011-03-31	273
2011-06-30	263
2011-09-30	282
2011-12-31	324
2012-03-31	277
2012-06-30	381
2012-09-30	610
2012-12-31	573
2013-03-31	612
2013-06-30	597
2013-09-30	638
2013-12-31	654
2014-03-31	604
2014-06-30	623
2014-09-30	559
2014-12-31	548
2015-03-31	462
2015-06-30	424