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Condensed Schedule of Investments	Mar. 31, 2021 USD ($) contract
Fair Value/ Unrealized Gain (Loss) on Open Commodity Contracts	$ 6,326,190
U.S. Treasury Bills, 0.04%, 5/06/2021 [Member]
Shares/Principal Amount	50,000,000
Market Value	$ 49,998,077
% of Partners' Capital	18.26%
Money Market Funds [Member]
Market Value	$ 194,043,000
% of Partners' Capital	70.88%
Money Market Funds [Member] | Goldman Sachs Financial Square Government Fund Institutional Shares [Member]
Shares/Principal Amount	$ 1,103,000
Market Value	$ 1,103,000
% of Partners' Capital	0.40%
Money Market Funds [Member] | Morgan Stanley Institutional Liquidity Funds Government Portfolio Institutional Shares [Member]
Shares/Principal Amount	$ 172,900,000
Market Value	$ 172,900,000
% of Partners' Capital	63.16%
Money Market Funds [Member] | RBC U.S. Government Money Market Fund Institutional Shares [Member]
Shares/Principal Amount	$ 20,040,000
Market Value	$ 20,040,000
% of Partners' Capital	7.32%
Open Commodity Futures Contracts, Long [Member] | United States Contracts | NYMEX Natural Gas Futures NG May 2021 contracts, expiring April 2021
Notional Amount	$ 267,435,570
Number of Contracts | contract	10,497
Fair Value/ Unrealized Gain (Loss) on Open Commodity Contracts	$ 6,326,190
% of Partners' Capital	2.31%
Cash Equivalents [Member] | Money Market Funds [Member]
Market Value	$ 244,041,077
% of Partners' Capital	89.14%

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