Condensed Statements of Cash Flows (Unaudited) - USD ($)	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Cash Flows from Operating Activities:
Net income (loss)	$ (78,883,355)	$ 19,896,460
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
Unrealized (gain) loss on open futures contracts	12,321,580	(6,341,280)
(Increase) decrease in receivable from General Partner	(56,591)	(6,005)
(Increase) decrease in dividends receivable	8,914	(49,321)
(Increase) decrease in interest receivable	4,670	(75)
(Increase) decrease in prepaid insurance	(7,587)	1,544
(Increase) decrease in ETF transaction fees receivable	(1,050)	0
Increase (decrease) in General Partner management fees payable	3,710	3,443
Increase (decrease) in professional fees payable	(53,133)	(83,543)
Increase (decrease) in brokerage commissions payable	300	0
Increase (decrease) in directors' fees payable	(199)	69
Increase (decrease) in insurance payable	0	13
Net cash provided by (used in) operating activities	(66,662,741)	13,421,305
Cash Flows from Financing Activities:
Addition of partnership shares	109,964,533	7,937,858
Redemption of partnership shares	(2,180,105)	(7,298,509)
Net cash provided by (used in) financing activities	107,784,428	639,349
Net Increase (Decrease) in Cash and Cash Equivalents	41,121,687	14,060,654
Total Cash, Cash Equivalents and Equity in Trading Accounts, beginning of period	83,603,440	80,057,642
Total Cash, Cash Equivalents and Equity in Trading Accounts, end of period	$ 124,725,127	$ 94,118,296

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