Condensed Statements of Cash Flows (USD $)	3 Months Ended
Mar. 31, 2013	Mar. 31, 2012
Cash Flows from Operating Activities:
Net income	$ 3,240,912	$ 9,156,188
Adjustments to reconcile net income to net cash provided by operating activities:
Decrease in commodity futures trading account - cash and cash equivalents	4,537,739	17,845,169
Unrealized gain on open futures contracts	(2,312,560)	(7,301,720)
(Increase) decrease in dividend receivable	823	(436)
Increase in interest receivable	0	(35)
(Increase) decrease in other assets	23,379	(6,200)
Decrease investment payable	0	(33)
Decrease in professional fees payable	(82,104)	(123,586)
Increase in General Partner management fees payable	547	669
Increase in other liabilities	233	6,955
Net cash provided by operating activities	5,408,969	19,576,971
Cash Flows from Financing Activities:
Addition of partnership units	20,455,450	18,020,754
Redemption of partnership units	(20,639,699)	(24,885,132)
Net cash used in financing activities	(184,249)	(6,864,378)
Net Increase in Cash and Cash Equivalents	5,224,720	12,712,593
Cash and Cash Equivalents, beginning of period	86,708,443	123,736,412
Cash and Cash Equivalents, end of period	$ 91,933,163	$ 136,449,005

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.