Quarter	US dollars
1999-03-31	144789
1999-06-30	142732
1999-09-30	150570
1999-12-31	145459
2000-03-31	163645
2000-06-30	169914
2000-09-30	184846
2000-12-31	185168
2001-03-31	199636
2001-06-30	205959
2001-09-30	206697
2001-12-31	191406
2002-03-31	176086
2002-06-30	185500
2002-09-30	182388
2002-12-31	193104
2003-03-31	205291
2003-06-30	200630
2003-09-30	211238
2003-12-31	234612
2004-03-31	261362
2004-06-30	272425
2004-09-30	303026
2004-12-31	300679
2005-03-31	329656
2005-06-30	335614
2005-09-30	372719
2005-12-31	377297
2006-03-31	427475
2006-06-30	449989
2006-09-30	495760
2006-12-31	497198
2007-03-31	535747
2007-06-30	531172
2007-09-30	591623
2007-12-31	628478
2008-03-31	593490
2008-06-30	544357
2008-09-30	566243
2008-12-31	404752
2009-03-31	367847
2009-06-30	371638
2009-09-30	364039
2009-12-31	350983
2010-03-31	361617
2010-06-30	361358
2010-09-30	363742
2010-12-31	375496
2011-03-31	414676
2011-06-30	408104
2011-09-30	405332
2011-12-31	418612
2012-03-31	457387
2012-06-30	464548
2012-09-30	450459
2012-12-31	421427
2013-03-31	450518
2013-06-30	426762
2013-09-30	446388
2013-12-31	460942
2014-03-31	475869
2014-06-30	490516
2014-09-30	484023
2014-12-31	462105
2015-03-31	452209
2015-06-30	465898
2015-09-30	480926
2015-12-31	466724
2016-03-31	454734
2016-06-30	459896
2016-09-30	458436
2016-12-31	428273
2017-03-31	478329
2017-06-30	474033
2017-09-30	474277
2017-12-31	475665
2018-03-31	510350
2018-06-30	461476
2018-09-30	485261
2018-12-31	488759
2019-03-31	538734
2019-06-30	552324
2019-09-30	526557
2019-12-31	514165
2020-03-31	566829
2020-06-30	488765
2020-09-30	492560
2020-12-31	513125
2021-03-31	534086
2021-06-30	537030
2021-09-30	558505
2021-12-31	560380
2022-03-31	587154
2022-06-30	573741
2022-09-30	570412
2022-12-31	539150
2023-03-31	557378
2023-06-30	551811
2023-09-30	528827