Quarter	US dollars
1999-03-31	9572
1999-06-30	11269
1999-09-30	13187
1999-12-31	14360
2000-03-31	15944
2000-06-30	15474
2000-09-30	15372
2000-12-31	16365
2001-03-31	16378
2001-06-30	17281
2001-09-30	20086
2001-12-31	18869
2002-03-31	20185
2002-06-30	21148
2002-09-30	21422
2002-12-31	23614
2003-03-31	28615
2003-06-30	33878
2003-09-30	33725
2003-12-31	36178
2004-03-31	44805
2004-06-30	45325
2004-09-30	49572
2004-12-31	61190
2005-03-31	62444
2005-06-30	67217
2005-09-30	69820
2005-12-31	68925
2006-03-31	75039
2006-06-30	75529
2006-09-30	93978
2006-12-31	105184
2007-03-31	129189
2007-06-30	134316
2007-09-30	152511
2007-12-31	158067
2008-03-31	168505
2008-06-30	161462
2008-09-30	147044
2008-12-31	126822
2009-03-31	120892
2009-06-30	124722
2009-09-30	125663
2009-12-31	124342
2010-03-31	122047
2010-06-30	103509
2010-09-30	113879
2010-12-31	149098
2011-03-31	159765
2011-06-30	159724
2011-09-30	146300
2011-12-31	146292
2012-03-31	144850
2012-06-30	132883
2012-09-30	132054
2012-12-31	133589
2013-03-31	129737
2013-06-30	127630
2013-09-30	120477
2013-12-31	116291
2014-03-31	108672
2014-06-30	108590
2014-09-30	106906
2014-12-31	105484
2015-03-31	107668
2015-06-30	112948
2015-09-30	114941
2015-12-31	114848
2016-03-31	115826
2016-06-30	100920
2016-09-30	102503
2016-12-31	102973
2017-03-31	101505
2017-06-30	107317
2017-09-30	107035
2017-12-31	99543
2018-03-31	115347
2018-06-30	108773
2018-09-30	119286
2018-12-31	135074
2019-03-31	132717
2019-06-30	130647
2019-09-30	128783
2019-12-31	136631
2020-03-31	134585
2020-06-30	134079
2020-09-30	143101
2020-12-31	145077
2021-03-31	146223
2021-06-30	135104
2021-09-30	138122
2021-12-31	141022
2022-03-31	137982
2022-06-30	131494
2022-09-30	120293
2022-12-31	112975
2023-03-31	112704
2023-06-30	118746
2023-09-30	114745