Quarter	US Dollars, sum over component sub-periods
1997-01-01	-4515835542.20301000
1997-04-01	30607038514.52509700
1997-07-01	7477539749.22137900
1997-10-01	1043148956.72364000
1998-01-01	307118059.59561200
1998-04-01	19432073048.16430000
1998-07-01	6572957918.93218000
1998-10-01	7407259566.36174000
1999-01-01	2874733992.51483000
1999-04-01	6482105776.17673000
1999-07-01	-10122790666.81250000
1999-10-01	9619113636.80597900
2000-01-01	7995854200.87149050
2000-04-01	5503364412.46272000
2000-07-01	-5955273914.87384000
2000-10-01	240848063.99529300
2001-01-01	25921839893.34640000
2001-04-01	5835290467.71456000
2001-07-01	-6276598506.82218000
2001-10-01	-4140665230.65524960
2002-01-01	-3863305485.51107000
2002-04-01	3303255465.10257960
2002-07-01	2774984637.92400000
2002-10-01	19031883510.28809700
2003-01-01	20504300467.92250000
2003-04-01	11473640474.44220000
2003-07-01	-11512094365.54390100
2003-10-01	-1576620501.57819000
2004-01-01	18634733399.21880000
2004-04-01	-6675858785.29261000
2004-07-01	13167011487.60840000
2004-10-01	20017851765.66489800
2005-01-01	43613381577.95280500
2005-04-01	38147984037.22550000
2005-07-01	-20648589150.30790000
2005-10-01	-16721203680.98350100
2006-01-01	54984451482.98350500
2006-04-01	39188418829.79610400
2006-07-01	-3683434854.89250000
2006-10-01	22248264241.92820000
2007-01-01	3626544941.03642000
2007-04-01	68423082438.10599500
2007-07-01	-5143409323.69875050
2007-10-01	-628896862.81679310
2008-01-01	28800041735.60440000
2008-04-01	37675279122.44960000
2008-07-01	-37889607252.96370000
2008-10-01	-68073350838.60660000
2009-01-01	37864725328.66530000
2009-04-01	2685514714.51584000
2009-07-01	-3886461293.75137000
2009-10-01	-98413493880.32880000
2010-01-01	-16428098405.70110100
2010-04-01	-29355398904.78930300
2010-07-01	-12469825729.39099900
2010-10-01	-10821915627.96190000
2011-01-01	10524901832.69080200
2011-04-01	-1285292376.70956000
2011-07-01	31732482971.65350000
2011-10-01	21511433329.15330000
2012-01-01	15553333074.70970200
2012-04-01	21937214258.27950000
2012-07-01	-3488757941.58711000
2012-10-01	8723835678.47609900
2013-01-01	-3036157296.33442000
2013-04-01	-500201775.69623303
2013-07-01	-8568878443.32568100
2013-10-01	-21621291043.05119700
2014-01-01	7148488430.38344000
2014-04-01	18341943598.56620000
2014-07-01	-6608044748.98001000
2014-10-01	4875950583.70799000
2015-01-01	3834234889.20416000
2015-04-01	-13435161865.65739800
2015-07-01	-10006388528.73330000
2015-10-01	-3841994287.08492000
2016-01-01	5574593628.98109000
2016-04-01	5139068461.29894000
2016-07-01	-20616853635.23000000
2016-10-01	16555928884.76579900
2017-01-01	22091129778.77300000
2017-04-01	-8139449207.63581000
2017-07-01	2233881119.58539000
2017-10-01	11377174668.27369900
2018-01-01	12423952713.90320000
2018-04-01	17186740222.50359700