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Condensed Schedule of Investments	Jun. 30, 2020 USD ($)
Fair Value/ Unrealized Gain (Loss) on Open Commodity Contracts	$ 1,356,010
Market Value	$ 368,750,955
% of Partners' Capital	96.18%
Money Market Funds [Member]
Market Value	$ 268,871,004
% of Partners' Capital	70.13%
Money Market Funds [Member] | Fidelity Investments Money Market Funds Government Portfolio [Member]
Principal Amount	$ 103,921
Market Value	$ 103,921
% of Partners' Capital	0.03%
Money Market Funds [Member] | Goldman Sachs Financial Square Funds - Government Fund - Class FS [Member]
Principal Amount	$ 268,149,233
Market Value	$ 268,149,233
% of Partners' Capital	69.94%
Open Commodity Futures Contracts, Long [Member] | United States Contracts | NYMEX Natural Gas Futures NG May 2020 contracts, expiring April 2020
Notional Amount	$ 382,025,440	[1]
Number of Contracts	21,895	[1]
Fair Value/ Unrealized Gain (Loss) on Open Commodity Contracts	$ 1,356,010	[1]
% of Partners' Capital	0.35%	[1]
Cash Equivalents [Member]
Market Value	$ 99,879,951
% of Partners' Capital	26.05%
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills, 1.54%, 7/02/2020 [Member]
Principal Amount	$ 10,000,000
Market Value	$ 9,999,576
% of Partners' Capital	2.61%
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills, 1.51%, 7/09/2020 [Member]
Principal Amount	$ 10,000,000
Market Value	$ 9,996,661
% of Partners' Capital	2.61%
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills, 1.54%, 7/16/2020 [Member]
Principal Amount	$ 10,000,000
Market Value	$ 9,993,625
% of Partners' Capital	2.61%
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills, 1.53%, 7/23/2020 [Member]
Principal Amount	$ 10,000,000
Market Value	$ 9,990,742
% of Partners' Capital	2.61%
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills, 1.53%, 7/30/2020 [Member]
Principal Amount	$ 10,000,000
Market Value	$ 9,987,755
% of Partners' Capital	2.60%
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills, 1.53%, 8/06/2020 [Member]
Principal Amount	$ 10,000,000
Market Value	$ 9,984,800
% of Partners' Capital	2.60%
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills, 1.52%, 8/13/2020 [Member]
Principal Amount	$ 10,000,000
Market Value	$ 9,982,000
% of Partners' Capital	2.60%
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills, 1.52%, 8/20/2020 [Member]
Principal Amount	$ 10,000,000
Market Value	$ 9,979,028
% of Partners' Capital	2.60%
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills, 1.42%, 8/27/2020 [Member]
Principal Amount	$ 10,000,000
Market Value	$ 9,977,675
% of Partners' Capital	2.60%
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills, 0.67%, 9/03/2020 [Member]
Principal Amount	$ 10,000,000
Market Value	$ 9,988,089
% of Partners' Capital	2.61%
Cash Equivalents [Member] | United States Contracts | Money Market Funds [Member] | RBC U.S. Government Money Market Fund - Institutional Share Class [Member]
Principal Amount	$ 617,849
Market Value	$ 617,850
% of Partners' Capital	0.16%
[1] *     Collateral amounted to $86,405,619 on open commodity futures contracts.

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