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Statements of Cash Flows - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Cash Flows from Operating Activities:
Net income (loss)	$ (77,617,254)	$ 110,037,462	$ (193,443,975)
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
Unrealized (gain) loss on open futures contracts	(46,252,567)	122,742,937	(18,286,173)
(Increase) decrease in dividends receivable	(62,127)	(61,099)	(2,090)
(Increase) decrease in interest receivable	4,443	1,903	(11,573)
(Increase) decrease in prepaid insurance	635	(3,646)	(79)
(Increase) decrease in prepaid registration fees	(392,476)	83,258	29,526
(Increase) decrease in ETF transaction fees receivable		1,000
Increase (decrease) in payable due to Broker			(44,770,339)
Increase (decrease) in General Partner management fees payable	26,513	(131,834)	9,112
Increase (decrease) in professional fees payable	(77,219)	(28,822)	455,541
Increase (decrease) in brokerage commissions payable		(36,500)	(12,400)
Increase (decrease) in directors' fees payable	2,089	(4,301)	3,007
Increase (decrease) in license fees payable	(2,045)	(8,116)	(7,138)
Net cash provided by (used in) operating activities	(124,370,008)	232,592,242	(256,036,581)
Cash Flows from Financing Activities:
Addition of partnership shares	914,876,988	1,744,841,011	1,786,316,120
Redemption of partnership shares	(691,299,703)	(2,269,580,373)	(1,446,127,327)
Net cash provided by (used in) financing activities	223,577,285	(524,739,362)	340,188,793
Net Increase (Decrease) in Cash and Cash Equivalents	99,207,277	(292,147,120)	84,152,212
Total Cash, Cash Equivalents and Equity in Trading Accounts, beginning of year	359,791,174	651,938,294	567,786,082
Total Cash, Cash Equivalents and Equity in Trading Accounts, end of year	$ 458,998,451	$ 359,791,174	$ 651,938,294

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