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Condensed Schedule of Investments	Mar. 31, 2019 USD ($) Contracts
Value/ Unrealized Gain (Loss) on Open Commodity Contracts	$ (16,887,660)
Open Futures Contracts - Long [Member] | United States [Member]
Notional Amount	$ 271,747,540	[1]
Number of Contracts | Contracts	13,324	[1]
Value/ Unrealized Gain (Loss) on Open Commodity Contracts	$ (16,887,660)	[1]
% of Partners' Capital	(6.63%)	[1]
Open Futures Contracts - Long [Member] | United States [Member] | NYMEX Natural Gas Futures NG May 2019 contracts expiring April 2019 [Member]
Notional Amount	$ 236,331,290
Number of Contracts | Contracts	8,324
Value/ Unrealized Gain (Loss) on Open Commodity Contracts	$ (14,746,410)
% of Partners' Capital	(5.79%)
Open Futures Contracts - Long [Member] | United States [Member] | ICE Natural Gas Futures LD1 H May 2019 contracts expiring May 2019 [Member]
Notional Amount	$ 35,416,250
Number of Contracts | Contracts	5,000
Value/ Unrealized Gain (Loss) on Open Commodity Contracts	$ (2,141,250)
% of Partners' Capital	(0.84%)
Cash Equivalents [Member] | United States Treasury Obligations [Member]
Market Value	$ 258,389,773
% of Partners' Capital	101.38%
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.37%, 4/04/2019 [Member]
Principal Amount	$ 10,000,000
Market Value	$ 9,998,046
% of Partners' Capital	3.92%
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.41%, 4/11/2019 [Member]
Principal Amount	$ 10,000,000
Market Value	$ 9,993,375
% of Partners' Capital	3.92%
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.42%, 4/18/2019 [Member]
Principal Amount	$ 5,000,000
Market Value	$ 4,994,345
% of Partners' Capital	1.96%
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.43%, 4/25/2019 [Member]
Principal Amount	$ 10,000,000
Market Value	$ 9,984,000
% of Partners' Capital	3.92%
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.47%, 5/09/2019 [Member]
Principal Amount	$ 15,000,000
Market Value	$ 14,961,446
% of Partners' Capital	5.87%
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.48%, 5/16/2019 [Member]
Principal Amount	$ 10,000,000
Market Value	$ 9,969,375
% of Partners' Capital	3.91%
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.50%, 5/23/2019 [Member]
Principal Amount	$ 20,000,000
Market Value	$ 19,928,789
% of Partners' Capital	7.82%
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.49%, 5/30/2019 [Member]
Principal Amount	$ 10,000,000
Market Value	$ 9,959,724
% of Partners' Capital	3.91%
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.51%, 6/06/2019 [Member]
Principal Amount	$ 10,000,000
Market Value	$ 9,954,625
% of Partners' Capital	3.91%
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.51%, 6/13/2019 [Member]
Principal Amount	$ 10,000,000
Market Value	$ 9,949,711
% of Partners' Capital	3.90%
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.49%, 6/20/2019 [Member]
Principal Amount	$ 10,000,000
Market Value	$ 9,945,333
% of Partners' Capital	3.90%
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.49%, 6/27/2019 [Member]
Principal Amount	$ 10,000,000
Market Value	$ 9,940,550
% of Partners' Capital	3.90%
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.47%, 7/05/2019 [Member]
Principal Amount	$ 10,000,000
Market Value	$ 9,935,743
% of Partners' Capital	3.90%
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.48%, 7/11/2019 [Member]
Principal Amount	$ 10,000,000
Market Value	$ 9,931,194
% of Partners' Capital	3.90%
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.47%, 7/18/2019 [Member]
Principal Amount	$ 10,000,000
Market Value	$ 9,926,800
% of Partners' Capital	3.89%
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.47%, 7/25/2019 [Member]
Principal Amount	$ 10,000,000
Market Value	$ 9,922,055
% of Partners' Capital	3.89%
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.48%, 8/01/2019 [Member]
Principal Amount	$ 10,000,000
Market Value	$ 9,916,972
% of Partners' Capital	3.89%
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.46%, 8/08/2019 [Member]
Principal Amount	$ 10,000,000
Market Value	$ 9,912,925
% of Partners' Capital	3.89%
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.47%, 8/15/2019 [Member]
Principal Amount	$ 10,000,000
Market Value	$ 9,907,822
% of Partners' Capital	3.89%
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.47%, 8/22/2019 [Member]
Principal Amount	$ 15,000,000
Market Value	$ 14,854,915
% of Partners' Capital	5.83%
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.48%, 8/29/2019 [Member]
Principal Amount	$ 10,000,000
Market Value	$ 9,897,917
% of Partners' Capital	3.88%
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.48%, 9/05/2019 [Member]
Principal Amount	$ 10,000,000
Market Value	$ 9,893,153
% of Partners' Capital	3.88%
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.48%, 9/12/2019 [Member]
Principal Amount	$ 5,000,000
Market Value	$ 4,944,308
% of Partners' Capital	1.94%
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.46%, 9/19/2019 [Member]
Principal Amount	$ 10,000,000
Market Value	$ 9,884,575
% of Partners' Capital	3.88%
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.41%, 9/26/2019 [Member]
Principal Amount	$ 10,000,000
Market Value	$ 9,882,075
% of Partners' Capital	3.88%
[1] Collateral amounted to $77,620,675 on open futures contracts.

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