Condensed Statements of Cash Flows - USD ($)	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014
Cash Flows from Operating Activities:
Net income (loss)	$ (2,620,154)	$ 742,547
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	2,567,618	(1,292,918)
Unrealized (gain) loss on open futures contracts	(2,579,334)	1,612,110
(Increase) decrease in receivable from General Partner	1,418	45,092
(Increase) decrease in dividends receivable	1	425
(Increase) decrease in directors' fees and insurance receivable	(423)	(1,102)
(Increase) decrease in ETF transaction fees receivable	350	0
Increase (decrease) in General Partner management fees payable	(2,110)	(8,536)
Increase (decrease) in professional fees payable	(18,646)	(78,142)
Increase (decrease) in brokerage commissions payable	0	(1,260)
Increase (decrease) in license fees payable	(88)	(429)
Net cash provided by (used in) operating activities	(2,651,368)	1,017,787
Cash Flows from Financing Activities:
Addition of partnership shares	10,347,656	0
Redemption of partnership shares	(9,882,640)	(11,987,259)
Net cash provided by (used in) financing activities	465,016	(11,987,259)
Net Increase (Decrease) in Cash and Cash Equivalents	(2,186,352)	(10,969,472)
Cash and Cash Equivalents, beginning of period	15,113,447	25,514,584
Cash and Cash Equivalents, end of period	$ 12,927,095	$ 14,545,112