Quarter	US dollars
1999-03-31	32188
1999-06-30	31260
1999-09-30	29911
1999-12-31	26557
2000-03-31	29624
2000-06-30	27566
2000-09-30	27879
2000-12-31	24047
2001-03-31	23959
2001-06-30	25704
2001-09-30	23387
2001-12-31	21220
2002-03-31	26885
2002-06-30	27145
2002-09-30	29840
2002-12-31	27294
2003-03-31	35187
2003-06-30	34114
2003-09-30	38551
2003-12-31	39588
2004-03-31	52139
2004-06-30	50596
2004-09-30	59825
2004-12-31	58890
2005-03-31	67156
2005-06-30	55720
2005-09-30	70039
2005-12-31	54772
2006-03-31	71829
2006-06-30	70559
2006-09-30	83323
2006-12-31	69762
2007-03-31	92126
2007-06-30	101307
2007-09-30	96405
2007-12-31	101989
2008-03-31	126651
2008-06-30	103770
2008-09-30	94152
2008-12-31	72641
2009-03-31	68943
2009-06-30	71568
2009-09-30	76353
2009-12-31	85011
2010-03-31	97199
2010-06-30	103401
2010-09-30	106670
2010-12-31	107688
2011-03-31	126060
2011-06-30	135776
2011-09-30	133896
2011-12-31	123885
2012-03-31	121286
2012-06-30	117498
2012-09-30	114885
2012-12-31	118700
2013-03-31	143936
2013-06-30	153474
2013-09-30	147731
2013-12-31	152961
2014-03-31	169473
2014-06-30	164539
2014-09-30	152096
2014-12-31	135015
2015-03-31	134936
2015-06-30	132087
2015-09-30	124395
2015-12-31	113280
2016-03-31	110671
2016-06-30	110442
2016-09-30	104559
2016-12-31	105272
2017-03-31	110027
2017-06-30	121334
2017-09-30	133095
2017-12-31	139571
2018-03-31	130864
2018-06-30	121276
2018-09-30	133234
2018-12-31	138407
2019-03-31	141174
2019-06-30	137369
2019-09-30	125225
2019-12-31	129423
2020-03-31	138069
2020-06-30	120714
2020-09-30	121396
2020-12-31	130069
2021-03-31	132300
2021-06-30	128923
2021-09-30	133509
2021-12-31	140832
2022-03-31	134635
2022-06-30	135333
2022-09-30	142421
2022-12-31	138854
2023-03-31	136297
2023-06-30	126535
2023-09-30	140703