Quarter	US Dollars, sum over component sub-periods
1988-07-01	3860111343.38357970
1988-10-01	3836627577.12662000
1989-01-01	1772485337.87933000
1989-04-01	3107625841.95473000
1989-07-01	1556262569.27046010
1989-10-01	1810842678.10695000
1990-01-01	2751107809.69382000
1990-04-01	16132697.00097370
1990-07-01	1197402391.07815000
1990-10-01	832278740.82070200
1991-01-01	2018192061.30355000
1991-04-01	-2776273484.72117000
1991-07-01	1604673774.41722000
1991-10-01	3353513144.88187030
1992-01-01	-470438780.21876600
1992-04-01	929116455.38654210
1992-07-01	379963975.10638600
1992-10-01	1455481246.05382010
1993-01-01	684144210.26113810
1993-04-01	1658357349.87559000
1993-07-01	2186311604.60345030
1993-10-01	3132674403.49570000
1994-01-01	2682584215.75714000
1994-04-01	1046743800.89421000
1994-07-01	-1993832056.97105000
1994-10-01	-375360092.71926004
1995-01-01	1331340625.22471000
1995-04-01	1602739714.99161000
1995-07-01	1831283582.74052000
1995-10-01	4914221384.21309000
1996-01-01	1536400135.89253000
1996-04-01	5044271275.75977000
1996-07-01	4886777218.57098000
1996-10-01	4652385291.80565000
1997-01-01	7058085697.88785000
1997-04-01	-1000990166.92454990
1997-07-01	6098767823.69393000
1997-10-01	4748108627.85702000
1998-01-01	579165678.93751910
1998-04-01	2507973921.59348000
1998-07-01	222985342.58777902
1998-10-01	5390159304.30332000
1999-01-01	4420540614.84676000
1999-04-01	1067598386.88636000
1999-07-01	2075420550.15304000
1999-10-01	11190429261.64709900
2000-01-01	1639198500.98352000
2000-04-01	976167053.80483400
2000-07-01	6168576176.45431000
2000-10-01	10458512455.93270000
2001-01-01	7417055595.88420000
2001-04-01	5134818368.79348900
2001-07-01	4256067089.96947960
2001-10-01	6006290164.13803000
2002-01-01	8398555839.90761100
2002-04-01	10212218287.07370000
2002-07-01	5124808920.13724000
2002-10-01	4609882202.82005000
2003-01-01	-2424700561.87461000
2003-04-01	14229664560.76820000
2003-07-01	5616286224.44827100
2003-10-01	20647315801.47100000
2004-01-01	14564372058.56430000
2004-04-01	9481235157.52823000
2004-07-01	1733640716.43908000
2004-10-01	16737864732.29149800
2005-01-01	7275668527.89030900
2005-04-01	-33558397326.21220000
2005-07-01	12619515244.54230000
2005-10-01	21811303179.56750000
2006-01-01	24438070957.31970000
2006-04-01	25982888882.49520000
2006-07-01	29522027913.23360000
2006-10-01	20341575432.13070000
2007-01-01	30753618958.86430000
2007-04-01	33697539117.55140300
2007-07-01	13844001353.03000000
2007-10-01	-2781675741.64174000
2008-01-01	26535563894.68360000
2008-04-01	24704545872.09340000
2008-07-01	16320794493.90580000
2008-10-01	2966984156.88071000
2009-01-01	7814015912.94822000
2009-04-01	29438313984.85310000
2009-07-01	27573697649.91660300
2009-10-01	42824742668.21360000
2010-01-01	7372684654.86972000
2010-04-01	21414673971.09770200
2010-07-01	11984795770.21070000
2010-10-01	34256039383.69790000
2011-01-01	23863740354.56540300
2011-04-01	48530103583.45879000
2011-07-01	48734605290.01250000
2011-10-01	-1682672837.72057000
2012-01-01	28234034794.69640000
2012-04-01	6435558202.96581000
2012-07-01	17770805384.62720000
2012-10-01	37057126857.87770000
2013-01-01	13001210368.69980000
2013-04-01	14633613080.56960000
2013-07-01	24933060920.30850200
2013-10-01	51788760845.95060000
2014-01-01	18078945019.83920000
2014-04-01	40128504706.16450500
2014-07-01	9441787824.25829000
2014-10-01	28501890856.22440000
2015-01-01	41553276386.31509400
2015-04-01	26339121917.07330000
2015-07-01	19520333413.00060000
2015-10-01	22064800920.52690000
2016-01-01	-7122605760.24950000
2016-04-01	11943898774.91289900
2016-07-01	-1972620764.01159000
2016-10-01	22942739241.39220000
2017-01-01	2439917743.25252960
2017-04-01	22301297999.54980000
2017-07-01	10428180806.96540000
2017-10-01	28591030854.34290000
2018-01-01	31291163658.58110000
2018-04-01	28277495937.53250000