Statements of Cash Flows - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Cash Flows from Operating Activities:
Net income (loss)	$ (3,146,483)	$ 2,869,424	$ (4,548,413)
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
(Increase) decrease in commodity futures trading account - cash and cash equivalents	(1,001,471)	3,622,568	1,202,800
Unrealized (gain) loss on open futures contracts	3,364,926	(5,217,980)	(2,497,914)
(Increase) decrease in receivable from General Partner	40,379	(12,970)	(22,856)
(Increase) decrease in dividends receivable	(831)	(1,337)	96
(Increase) decrease in interest receivable	(88)	0	0
(Increase) decrease in directors' fees and insurance receivable	(66)	1,197	(85)
(Increase) decrease in ETF transaction fees receivable	350	(350)	350
Increase (decrease) in payable due to Broker	(2,099,689)	2,099,689	0
Increase (decrease) in General Partner management fees payable	(4,944)	2,510	(3,142)
Increase (decrease) in professional fees payable	(29,606)	27,360	(5,108)
Increase (decrease) in brokerage commissions payable	(620)	0	220
Increase (decrease) in directors' fees and insurance payable	(106)	106	0
Increase (decrease) in license fees payable	(413)	(84)	(170)
Net cash provided by (used in) operating activities	(2,878,662)	3,390,133	(5,874,222)
Cash Flows from Financing Activities:
Addition of partnership shares	1,021,619	1,418,858	11,863,149
Redemption of partnership shares	(5,986,374)	(967,707)	(9,882,640)
Net cash provided by (used in) financing activities	(4,964,755)	451,151	1,980,509
Net Increase (Decrease) in Cash and Cash Equivalents	(7,843,417)	3,841,284	(3,893,713)
Cash and Cash Equivalents, beginning of year	15,061,018	11,219,734	15,113,447
Cash and Cash Equivalents, end of year	$ 7,217,601	$ 15,061,018	$ 11,219,734