Statements of Operations (Unaudited) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Investment Income:
Interest	$ 57,392	$ 73,513	$ 123,178	$ 183,856
Total Investment Income	57,392	73,513	123,178	183,856
Expenses:
Management fees	631,736	785,305	1,320,011	1,559,406
Brokerage commissions	42,716	45,188	83,938	85,276
Custodian's fees and expenses	32,769	31,605	59,045	35,442
Trustees' fees and expenses	25,111	27,500	56,361	60,625
Professional fees	119,326	53,888	217,903	138,195
Shareholder reporting expense	39,680	53,382	71,088	110,305
Other expenses	6,982	7,888	11,343	19,247
Total expenses	898,320	1,004,756	1,819,689	2,008,496
Net investment income (loss)	(840,928)	(931,243)	(1,696,511)	(1,824,640)
Net realized gain (loss) from:
Short-term investments		10,899	(652)	10,899
Futures contracts	(22,226,328)	(7,066,543)	(16,939,576)	18,030,482
Call options written	1,659,694	2,963,912	4,236,174	5,357,510
Change in net unrealized appreciation (depreciation) of:
Short-term investments	(4,822)	10,559	(28,176)	(7,586)
Futures contracts	7,190,243	(9,779,337)	7,710,570	(22,956,284)
Call options written	(1,352,546)	(134,460)	(1,709,545)	2,364,079
Net realized gain (loss) and change in net unrealized appreciation (depreciation)	(14,733,759)	(13,994,970)	(6,731,205)	2,799,100
Net income (loss)	$ (15,574,687)	$ (14,926,213)	$ (8,427,716)	$ 974,460
Net income (loss) per weighted-average share	$ (1.69)	$ (1.61)	$ (0.91)	$ 0.11
Weighted-average shares outstanding	9,219,240	9,267,040	9,219,589	9,267,040