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Condensed Schedule of Investments	Mar. 31, 2020 USD ($)
Value/ Unrealized Gain (Loss) on Open Commodity Contracts	$ (29,219,350)
Open Futures Contracts - Long [Member] | United States Contracts | NYMEX Natural Gas Futures NG May 2020 contracts, expiring April 2020
Notional Amount	$ 357,137,350	[1]
Number of Contracts	19,995	[1]
Value/ Unrealized Gain (Loss) on Open Commodity Contracts	$ (29,219,350)	[1]
% of Partners' Capital	(8.91%)	[1]
Cash Equivalents [Member]
Market Value	$ 229,280,791
% of Partners' Capital	69.92%
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills, 1.70%, 4/02/2020 [Member]
Principal Amount	$ 10,000,000
Market Value	$ 9,999,531
% of Partners' Capital	3.05%
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills, 1.64%, 4/09/2020 [Member]
Principal Amount	$ 10,000,000
Market Value	$ 9,996,378
% of Partners' Capital	3.05%
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills, 1.60%, 4/16/2020 [Member]
Principal Amount	$ 10,000,000
Market Value	$ 9,993,375
% of Partners' Capital	3.05%
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills, 1.60%, 4/23/2020 [Member]
Principal Amount	$ 10,000,000
Market Value	$ 9,990,283
% of Partners' Capital	3.05%
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills, 1.59%, 4/30/2020 [Member]
Principal Amount	$ 10,000,000
Market Value	$ 9,987,312
% of Partners' Capital	3.05%
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills, 1.54%, 5/07/2020 [Member]
Principal Amount	$ 10,000,000
Market Value	$ 9,984,750
% of Partners' Capital	3.04%
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills, 1.55%, 5/14/2020 [Member]
Principal Amount	$ 10,000,000
Market Value	$ 9,981,606
% of Partners' Capital	3.04%
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills, 1.55%, 5/21/2020 [Member]
Principal Amount	$ 10,000,000
Market Value	$ 9,978,680
% of Partners' Capital	3.04%
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills, 1.58%, 5/28/2020 [Member]
Principal Amount	$ 10,000,000
Market Value	$ 9,975,142
% of Partners' Capital	3.04%
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills, 1.53%, 6/04/2020 [Member]
Principal Amount	$ 10,000,000
Market Value	$ 9,972,978
% of Partners' Capital	3.04%
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills, 1.53%, 6/11/2020 [Member]
Principal Amount	$ 10,000,000
Market Value	$ 9,969,973
% of Partners' Capital	3.04%
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills, 1.54%, 6/18/2020 [Member]
Principal Amount	$ 10,000,000
Market Value	$ 9,966,850
% of Partners' Capital	3.04%
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills, 1.57%, 6/25/2020 [Member]
Principal Amount	$ 10,000,000
Market Value	$ 9,963,167
% of Partners' Capital	3.04%
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	$ 9,961,028
% of Partners' Capital	3.04%
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	$ 9,958,681
% of Partners' Capital	3.04%
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	$ 9,954,950
% of Partners' Capital	3.04%
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	$ 9,952,446
% of Partners' Capital	3.04%
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	$ 9,949,333
% of Partners' Capital	3.03%
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	$ 9,946,378
% of Partners' Capital	3.03%
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	$ 9,943,906
% of Partners' Capital	3.03%
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	$ 9,940,858
% of Partners' Capital	3.03%
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	$ 9,942,033
% of Partners' Capital	3.03%
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	$ 9,971,153
% of Partners' Capital	3.04%
[1] Collateral amounted to $73,321,026 on open futures contracts.

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