Quarter	US dollars
1999-03-31	28101
1999-06-30	29274
1999-09-30	24773
1999-12-31	19421
2000-03-31	18920
2000-06-30	18267
2000-09-30	19901
2000-12-31	19037
2001-03-31	22538
2001-06-30	20386
2001-09-30	22032
2001-12-31	28307
2002-03-31	29995
2002-06-30	32806
2002-09-30	37034
2002-12-31	42058
2003-03-31	43512
2003-06-30	54128
2003-09-30	71485
2003-12-31	77847
2004-03-31	78759
2004-06-30	87646
2004-09-30	96884
2004-12-31	119188
2005-03-31	141653
2005-06-30	146699
2005-09-30	142914
2005-12-31	152545
2006-03-31	156468
2006-06-30	191149
2006-09-30	155745
2006-12-31	165312
2007-03-31	188289
2007-06-30	194107
2007-09-30	194828
2007-12-31	198492
2008-03-31	223520
2008-06-30	171602
2008-09-30	180794
2008-12-31	148404
2009-03-31	123767
2009-06-30	116085
2009-09-30	104668
2009-12-31	142991
2010-03-31	124232
2010-06-30	100372
2010-09-30	104466
2010-12-31	121905
2011-03-31	126668
2011-06-30	131762
2011-09-30	91876
2011-12-31	84059
2012-03-31	87812
2012-06-30	80867
2012-09-30	80712
2012-12-31	75538
2013-03-31	94208
2013-06-30	91308
2013-09-30	99850
2013-12-31	97082
2014-03-31	100087
2014-06-30	117954
2014-09-30	135635
2014-12-31	123990
2015-03-31	119804
2015-06-30	116758
2015-09-30	128347
2015-12-31	115421
2016-03-31	116663
2016-06-30	120839
2016-09-30	111079
2016-12-31	126800
2017-03-31	112557
2017-06-30	110379
2017-09-30	128776
2017-12-31	150973
2018-03-31	139782
2018-06-30	130388
2018-09-30	130334
2018-12-31	131596
2019-03-31	129001
2019-06-30	121153
2019-09-30	97729
2019-12-31	111080
2020-03-31	115955
2020-06-30	106177
2020-09-30	106195
2020-12-31	116909
2021-03-31	121417
2021-06-30	133482
2021-09-30	130882
2021-12-31	163201
2022-03-31	162712
2022-06-30	157593
2022-09-30	129611
2022-12-31	127401
2023-03-31	124100
2023-06-30	119352
2023-09-30	109757