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Condensed Schedule of Investments	Sep. 30, 2019 USD ($)
Value/ Unrealized Gain (Loss) on Open Commodity Contracts	$ (36,647,195)
Open Futures Contracts - Long [Member] | United States Contracts | NYMEX Natural Gas Futures NG November 2019 contracts, expiring October 2019 [Member]
Notional Amount	$ 293,483,095	[1]
Number of Contracts	11,023	[1]
Value/ Unrealized Gain (Loss) on Open Commodity Contracts	$ (36,647,195)	[1]
% of Partners' Capital	(14.27%)	[1]
Cash Equivalents [Member]
Market Value	$ 258,738,875
% of Partners' Capital	100.74%
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.40%, 10/03/2019 [Member]
Principal Amount	$ 10,000,000
Market Value	$ 9,998,681
% of Partners' Capital	3.89%
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.41%, 10/10/2019 [Member]
Principal Amount	$ 10,000,000
Market Value	$ 9,994,037
% of Partners' Capital	3.89%
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.40%, 10/24/2019 [Member]
Principal Amount	$ 10,000,000
Market Value	$ 9,984,858
% of Partners' Capital	3.89%
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.37%, 10/31/2019 [Member]
Principal Amount	$ 10,000,000
Market Value	$ 9,980,500
% of Partners' Capital	3.89%
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.40%, 11/07/2019 [Member]
Principal Amount	$ 10,000,000
Market Value	$ 9,975,590
% of Partners' Capital	3.88%
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.38%, 11/14/2019 [Member]
Principal Amount	$ 10,000,000
Market Value	$ 9,971,217
% of Partners' Capital	3.88%
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.37%, 11/21/2019 [Member]
Principal Amount	$ 10,000,000
Market Value	$ 9,966,850
% of Partners' Capital	3.88%
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.33%, 11/29/2019 [Member]
Principal Amount	$ 10,000,000
Market Value	$ 9,962,224
% of Partners' Capital	3.88%
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.20%, 12/05/2019 [Member]
Principal Amount	$ 10,000,000
Market Value	$ 9,960,639
% of Partners' Capital	3.88%
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.16%, 12/12/2019 [Member]
Principal Amount	$ 10,000,000
Market Value	$ 9,957,200
% of Partners' Capital	3.88%
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.15%, 12/19/2019 [Member]
Principal Amount	$ 10,000,000
Market Value	$ 9,953,368
% of Partners' Capital	3.88%
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.07%, 12/26/2019 [Member]
Principal Amount	$ 10,000,000
Market Value	$ 9,951,147
% of Partners' Capital	3.87%
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.05%, 1/02/2020 [Member]
Principal Amount	$ 10,000,000
Market Value	$ 9,947,688
% of Partners' Capital	3.87%
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.03%, 1/09/2020 [Member]
Principal Amount	$ 10,000,000
Market Value	$ 9,944,167
% of Partners' Capital	3.87%
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.01%, 1/16/2020 [Member]
Principal Amount	$ 10,000,000
Market Value	$ 9,941,001
% of Partners' Capital	3.87%
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.04%, 1/23/2020 [Member]
Principal Amount	$ 10,000,000
Market Value	$ 9,936,128
% of Partners' Capital	3.87%
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.02%, 1/30/2020 [Member]
Principal Amount	$ 10,000,000
Market Value	$ 9,932,845
% of Partners' Capital	3.87%
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 1.90%, 2/06/2020 [Member]
Principal Amount	$ 10,000,000
Market Value	$ 9,933,244
% of Partners' Capital	3.87%
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 1.87%, 2/13/2020 [Member]
Principal Amount	$ 10,000,000
Market Value	$ 9,930,438
% of Partners' Capital	3.87%
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 1.85%, 2/20/2020 [Member]
Principal Amount	$ 10,000,000
Market Value	$ 9,927,619
% of Partners' Capital	3.86%
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 1.85%, 2/27/2020 [Member]
Principal Amount	$ 10,000,000
Market Value	$ 9,924,258
% of Partners' Capital	3.86%
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 1.83%, 3/05/2020 [Member]
Principal Amount	$ 20,000,000
Market Value	$ 19,842,570
% of Partners' Capital	7.73%
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 1.84%, 3/19/2020 [Member]
Principal Amount	$ 10,000,000
Market Value	$ 9,914,056
% of Partners' Capital	3.86%
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 1.88%, 3/26/2020 [Member]
Principal Amount	$ 10,000,000
Market Value	$ 9,908,550
% of Partners' Capital	3.86%
Cash Equivalents [Member] | United States Contracts
Market Value	$ 248,738,875
% of Partners' Capital	96.85%
Cash Equivalents [Member] | United States Contracts | Money Market Funds [Member] | Goldman Sachs Financial Square Funds - Government Fund - Class FS [Member]
Principal Amount	$ 10,000,000
Market Value	$ 10,000,000
% of Partners' Capital	3.89%
[1] Collateral amounted to $59,157,687 on open futures contracts.

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