Quarter	US dollars
1999-03-31	21529
1999-06-30	22809
1999-09-30	21877
1999-12-31	20673
2000-03-31	21351
2000-06-30	20117
2000-09-30	18101
2000-12-31	17586
2001-03-31	16392
2001-06-30	18071
2001-09-30	16575
2001-12-31	17770
2002-03-31	15550
2002-06-30	19160
2002-09-30	18390
2002-12-31	21936
2003-03-31	18866
2003-06-30	19808
2003-09-30	19209
2003-12-31	21788
2004-03-31	18841
2004-06-30	20233
2004-09-30	21434
2004-12-31	24488
2005-03-31	26463
2005-06-30	25522
2005-09-30	22151
2005-12-31	27691
2006-03-31	21871
2006-06-30	24875
2006-09-30	23794
2006-12-31	28784
2007-03-31	28630
2007-06-30	29501
2007-09-30	31189
2007-12-31	39755
2008-03-31	40576
2008-06-30	34376
2008-09-30	36810
2008-12-31	32560
2009-03-31	36974
2009-06-30	43650
2009-09-30	46928
2009-12-31	43780
2010-03-31	41462
2010-06-30	39724
2010-09-30	42300
2010-12-31	43399
2011-03-31	48122
2011-06-30	44066
2011-09-30	44939
2011-12-31	41436
2012-03-31	42112
2012-06-30	46153
2012-09-30	38709
2012-12-31	41331
2013-03-31	36297
2013-06-30	39914
2013-09-30	36042
2013-12-31	40745
2014-03-31	39080
2014-06-30	44998
2014-09-30	37871
2014-12-31	37639
2015-03-31	36617
2015-06-30	39573
2015-09-30	38545
2015-12-31	41784
2016-03-31	35018
2016-06-30	43593
2016-09-30	39390
2016-12-31	43543
2017-03-31	37742
2017-06-30	38268
2017-09-30	41686
2017-12-31	40915
2018-03-31	40120
2018-06-30	35730
2018-09-30	36292
2018-12-31	38366
2019-03-31	37593
2019-06-30	36293
2019-09-30	38236
2019-12-31	39543
2020-03-31	43211
2020-06-30	42530
2020-09-30	47672
2020-12-31	55577
2021-03-31	55989
2021-06-30	53378
2021-09-30	56197
2021-12-31	64399
2022-03-31	69648
2022-06-30	74194
2022-09-30	83579
2022-12-31	83180
2023-03-31	79660
2023-06-30	75089
2023-09-30	76750