Quarter	US dollars
1999-03-31	2291
1999-06-30	2419
1999-09-30	1619
1999-12-31	1470
2000-03-31	1310
2000-06-30	1818
2000-09-30	1635
2000-12-31	2502
2001-03-31	2270
2001-06-30	2195
2001-09-30	2022
2001-12-31	2078
2002-03-31	2334
2002-06-30	2948
2002-09-30	2625
2002-12-31	2908
2003-03-31	2827
2003-06-30	2885
2003-09-30	3306
2003-12-31	3337
2004-03-31	3723
2004-06-30	4075
2004-09-30	4482
2004-12-31	4309
2005-03-31	4020
2005-06-30	3934
2005-09-30	3407
2005-12-31	3875
2006-03-31	4898
2006-06-30	5406
2006-09-30	5529
2006-12-31	5281
2007-03-31	5812
2007-06-30	6875
2007-09-30	9985
2007-12-31	15913
2008-03-31	19410
2008-06-30	17701
2008-09-30	18452
2008-12-31	14476
2009-03-31	12079
2009-06-30	13899
2009-09-30	13341
2009-12-31	12471
2010-03-31	11482
2010-06-30	12133
2010-09-30	12448
2010-12-31	12539
2011-03-31	11782
2011-06-30	11854
2011-09-30	14748
2011-12-31	17752
2012-03-31	15417
2012-06-30	15117
2012-09-30	13839
2012-12-31	24256
2013-03-31	24236
2013-06-30	23598
2013-09-30	28723
2013-12-31	23132
2014-03-31	30418
2014-06-30	27297
2014-09-30	31966
2014-12-31	33797
2015-03-31	34019
2015-06-30	38742
2015-09-30	39015
2015-12-31	47747
2016-03-31	39764
2016-06-30	40727
2016-09-30	39207
2016-12-31	36395
2017-03-31	35538
2017-06-30	35840
2017-09-30	38070
2017-12-31	39538
2018-03-31	39967
2018-06-30	38339
2018-09-30	38978
2018-12-31	36831
2019-03-31	38195
2019-06-30	41545
2019-09-30	39472
2019-12-31	38264
2020-03-31	35505
2020-06-30	35332
2020-09-30	35036
2020-12-31	33230
2021-03-31	35644
2021-06-30	37035
2021-09-30	36841
2021-12-31	37522
2022-03-31	38046
2022-06-30	40513
2022-09-30	38817
2022-12-31	38230
2023-03-31	37713
2023-06-30	39716
2023-09-30	37960