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v3.19.1

Schedule of Investments | Dec. 31, 2018 USD ($) | Dec. 31, 2017 USD ($)
--- | --- | ---
Value/ Unrealized Gain (Loss) on Open Commodity Contracts | $ (67,021,257) |  | $ 55,721,680 |
Open Futures Contracts - Long [Member] | United States [Member] |  |  |  |
Notional Amount | $ 315,010,257 | [1] | $ 596,359,780 | [2]
Number of Contracts | 12,935 | [1] | 37,082 | [2]
Value/ Unrealized Gain (Loss) on Open Commodity Contracts | $ (67,021,257) | [1] | $ 55,721,680 | [2]
% of Partners' Capital | (27.02%) | [1] | 8.55% | [2]
Open Futures Contracts - Long [Member] | United States [Member] | NYMEX Natural Gas Futures NG February 2019 contracts, expiring January 2019 [Member] |  |  |  |
Notional Amount | $ 259,275,882 |  |  |
Number of Contracts | 6,935 |  |  |
Value/ Unrealized Gain (Loss) on Open Commodity Contracts | $ (55,386,882) |  |  |
% of Partners' Capital | (22.33%) |  |  |
Open Futures Contracts - Long [Member] | United States [Member] | ICE Natural Gas Futures LD1 H February 2019 contracts, expiring February 2019 [Member] |  |  |  |
Notional Amount | $ 55,734,375 |  |  |
Number of Contracts | 6,000 |  |  |
Value/ Unrealized Gain (Loss) on Open Commodity Contracts | $ (11,634,375) |  |  |
% of Partners' Capital | (4.69%) |  |  |
Open Futures Contracts - Long [Member] | United States [Member] | NYMEX Natural Gas Futures NG February 2018 contracts, expiring January 2018 [Member] |  |  |  |
Notional Amount |  |  | $ 461,049,780 |
Number of Contracts |  |  | 17,082 |
Value/ Unrealized Gain (Loss) on Open Commodity Contracts |  |  | $ 43,381,680 |
% of Partners' Capital |  |  | 6.66% |
Open Futures Contracts - Long [Member] | United States [Member] | ICE Natural Gas Futures LD1 H February 2018 contracts, expiring February 2018 [Member] |  |  |  |
Notional Amount |  |  | $ 135,310,000 |
Number of Contracts |  |  | 20,000 |
Value/ Unrealized Gain (Loss) on Open Commodity Contracts |  |  | $ 12,340,000 |
% of Partners' Capital |  |  | 1.89% |
Cash Equivalents [Member] |  |  |  |
Market Value | $ 272,193,228 |  | $ 483,194,474 |
% of Partners' Capital | 109.75% |  | 74.10% |
Cash Equivalents [Member] | United States Treasury Obligations [Member] |  |  |  |
Market Value | $ 238,493,228 |  | $ 463,194,474 |
% of Partners' Capital | 96.16% |  | 71.04% |
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.10%, 1/03/2019 [Member] |  |  |  |
Principal Amount | $ 10,000,000 |  |  |
Market Value | $ 9,998,847 |  |  |
% of Partners' Capital | 4.03% |  |  |
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.10%, 1/10/2019 [Member] |  |  |  |
Principal Amount | $ 10,000,000 |  |  |
Market Value | $ 9,994,800 |  |  |
% of Partners' Capital | 4.03% |  |  |
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.13%, 1/17/2019 [Member] |  |  |  |
Principal Amount | $ 10,000,000 |  |  |
Market Value | $ 9,990,622 |  |  |
% of Partners' Capital | 4.03% |  |  |
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.15%, 1/24/2019 [Member] |  |  |  |
Principal Amount | $ 10,000,000 |  |  |
Market Value | $ 9,986,423 |  |  |
% of Partners' Capital | 4.03% |  |  |
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.18%, 1/31/2019 [Member] |  |  |  |
Principal Amount | $ 10,000,000 |  |  |
Market Value | $ 9,982,042 |  |  |
% of Partners' Capital | 4.02% |  |  |
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.20%, 2/07/2019 [Member] |  |  |  |
Principal Amount | $ 10,000,000 |  |  |
Market Value | $ 9,977,646 |  |  |
% of Partners' Capital | 4.02% |  |  |
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.20%, 2/21/2019 [Member] |  |  |  |
Principal Amount | $ 10,000,000 |  |  |
Market Value | $ 9,969,117 |  |  |
% of Partners' Capital | 4.02% |  |  |
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.38%, 3/07/2019 [Member] |  |  |  |
Principal Amount | $ 10,000,000 |  |  |
Market Value | $ 9,957,479 |  |  |
% of Partners' Capital | 4.01% |  |  |
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.28%, 3/14/2019 [Member] |  |  |  |
Principal Amount | $ 10,000,000 |  |  |
Market Value | $ 9,954,900 |  |  |
% of Partners' Capital | 4.01% |  |  |
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.33%, 3/21/2019 [Member] |  |  |  |
Principal Amount | $ 10,000,000 |  |  |
Market Value | $ 9,949,528 |  |  |
% of Partners' Capital | 4.01% |  |  |
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.34%, 3/28/2019 [Member] |  |  |  |
Principal Amount | $ 10,000,000 |  |  |
Market Value | $ 9,944,817 |  |  |
% of Partners' Capital | 4.01% |  |  |
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 | $ 9,939,421 |  |  |
% of Partners' Capital | 4.01% |  |  |
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 | $ 9,933,750 |  |  |
% of Partners' Capital | 4.01% |  |  |
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 | $ 4,964,408 |  |  |
% of Partners' Capital | 2.00% |  |  |
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 | $ 9,924,000 |  |  |
% of Partners' Capital | 4.00% |  |  |
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 | $ 14,870,133 |  |  |
% of Partners' Capital | 6.00% |  |  |
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 | $ 9,908,125 |  |  |
% of Partners' Capital | 3.99% |  |  |
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 | $ 19,805,539 |  |  |
% of Partners' Capital | 7.99% |  |  |
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 | $ 9,898,287 |  |  |
% of Partners' Capital | 3.99% |  |  |
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 | $ 9,892,750 |  |  |
% of Partners' Capital | 3.99% |  |  |
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 | $ 9,887,711 |  |  |
% of Partners' Capital | 3.99% |  |  |
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 | $ 9,883,833 |  |  |
% of Partners' Capital | 3.99% |  |  |
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 | $ 9,879,050 |  |  |
% of Partners' Capital | 3.98% |  |  |
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 1.12%, 1/04/2018 [Member] |  |  |  |
Principal Amount |  |  | $ 10,000,000 |
Market Value |  |  | $ 9,999,071 |
% of Partners' Capital |  |  | 1.53% |
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 1.11%, 1/11/2018 [Member] |  |  |  |
Principal Amount |  |  | $ 15,000,000 |
Market Value |  |  | $ 14,995,396 |
% of Partners' Capital |  |  | 2.30% |
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 1.10%, 1/18/2018 [Member] |  |  |  |
Principal Amount |  |  | $ 15,000,000 |
Market Value |  |  | $ 14,992,279 |
% of Partners' Capital |  |  | 2.30% |
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 1.12%, 1/25/2018 [Member] |  |  |  |
Principal Amount |  |  | $ 10,000,000 |
Market Value |  |  | $ 9,992,567 |
% of Partners' Capital |  |  | 1.53% |
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 1.12%, 2/01/2018 [Member] |  |  |  |
Principal Amount |  |  | $ 10,000,000 |
Market Value |  |  | $ 9,990,399 |
% of Partners' Capital |  |  | 1.53% |
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 1.13%, 2/08/2018 [Member] |  |  |  |
Principal Amount |  |  | $ 10,000,000 |
Market Value |  |  | $ 9,988,125 |
% of Partners' Capital |  |  | 1.53% |
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 1.12%, 2/15/2018 [Member] |  |  |  |
Principal Amount |  |  | $ 10,000,000 |
Market Value |  |  | $ 9,986,125 |
% of Partners' Capital |  |  | 1.53% |
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 1.10%, 2/22/2018 [Member] |  |  |  |
Principal Amount |  |  | $ 15,000,000 |
Market Value |  |  | $ 14,976,383 |
% of Partners' Capital |  |  | 2.30% |
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 1.09%, 3/01/2018 [Member] |  |  |  |
Principal Amount |  |  | $ 20,000,000 |
Market Value |  |  | $ 19,964,436 |
% of Partners' Capital |  |  | 3.06% |
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 1.14%, 3/08/2018 [Member] |  |  |  |
Principal Amount |  |  | $ 10,000,000 |
Market Value |  |  | $ 9,979,237 |
% of Partners' Capital |  |  | 1.53% |
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 1.14%, 3/15/2018 [Member] |  |  |  |
Principal Amount |  |  | $ 10,000,000 |
Market Value |  |  | $ 9,977,086 |
% of Partners' Capital |  |  | 1.53% |
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 1.16%, 3/22/2018 [Member] |  |  |  |
Principal Amount |  |  | $ 15,000,000 |
Market Value |  |  | $ 14,961,667 |
% of Partners' Capital |  |  | 2.30% |
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 1.17%, 3/29/2018 [Member] |  |  |  |
Principal Amount |  |  | $ 15,000,000 |
Market Value |  |  | $ 14,957,950 |
% of Partners' Capital |  |  | 2.29% |
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 1.19%, 4/05/2018 [Member] |  |  |  |
Principal Amount |  |  | $ 25,000,000 |
Market Value |  |  | $ 24,922,646 |
% of Partners' Capital |  |  | 3.82% |
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 1.22%, 4/12/2018 [Member] |  |  |  |
Principal Amount |  |  | $ 25,000,000 |
Market Value |  |  | $ 24,914,781 |
% of Partners' Capital |  |  | 3.82% |
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 1.23%, 4/19/2018 [Member] |  |  |  |
Principal Amount |  |  | $ 25,000,000 |
Market Value |  |  | $ 24,908,687 |
% of Partners' Capital |  |  | 3.82% |
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 1.25%, 4/26/2018 [Member] |  |  |  |
Principal Amount |  |  | $ 25,000,000 |
Market Value |  |  | $ 24,900,972 |
% of Partners' Capital |  |  | 3.82% |
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 1.27%, 5/03/2018 [Member] |  |  |  |
Principal Amount |  |  | $ 15,000,000 |
Market Value |  |  | $ 14,935,950 |
% of Partners' Capital |  |  | 2.29% |
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 1.32%, 5/10/2018 [Member] |  |  |  |
Principal Amount |  |  | $ 20,000,000 |
Market Value |  |  | $ 19,906,117 |
% of Partners' Capital |  |  | 3.05% |
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 1.37%, 5/17/2018 [Member] |  |  |  |
Principal Amount |  |  | $ 20,000,000 |
Market Value |  |  | $ 19,897,433 |
% of Partners' Capital |  |  | 3.05% |
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 1.43%, 5/24/2018 [Member] |  |  |  |
Principal Amount |  |  | $ 20,000,000 |
Market Value |  |  | $ 19,887,586 |
% of Partners' Capital |  |  | 3.05% |
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 1.43%, 5/31/2018 [Member] |  |  |  |
Principal Amount |  |  | $ 20,000,000 |
Market Value |  |  | $ 19,881,667 |
% of Partners' Capital |  |  | 3.05% |
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 1.45%, 6/07/2018 [Member] |  |  |  |
Principal Amount |  |  | $ 20,000,000 |
Market Value |  |  | $ 19,874,400 |
% of Partners' Capital |  |  | 3.05% |
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 1.46%, 6/14/2018 [Member] |  |  |  |
Principal Amount |  |  | $ 25,000,000 |
Market Value |  |  | $ 24,835,431 |
% of Partners' Capital |  |  | 3.82% |
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 1.49%, 6/21/2018 [Member] |  |  |  |
Principal Amount |  |  | $ 30,000,000 |
Market Value |  |  | $ 29,789,100 |
% of Partners' Capital |  |  | 4.57% |
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 1.50%, 6/28/2018 [Member] |  |  |  |
Principal Amount |  |  | $ 30,000,000 |
Market Value |  |  | $ 29,778,983 |
% of Partners' Capital |  |  | 4.57% |
Cash Equivalents [Member] | United States [Member] | Money Market Funds [Member] |  |  |  |
Market Value | $ 33,700,000 |  | $ 20,000,000 |
% of Partners' Capital | 13.59% |  | 3.06% |
Cash Equivalents [Member] | United States [Member] | Money Market Funds [Member] | Fidelity Investments Money Market Funds - Government Portfolio [Member] |  |  |  |
Principal Amount | $ 2,500,000 |  | $ 10,000,000 |
Market Value | $ 2,500,000 |  | $ 10,000,000 |
% of Partners' Capital | 1.01% |  | 1.53% |
Cash Equivalents [Member] | United States [Member] | Money Market Funds [Member] | Goldman Sachs Financial Square Funds - Government Fund - Class FS [Member] |  |  |  |
Principal Amount | $ 31,200,000 |  | $ 10,000,000 |
Market Value | $ 31,200,000 |  | $ 10,000,000 |
% of Partners' Capital | 12.58% |  | 1.53% |
[1] | Collateral amounted to $100,299,442 on open futures contracts.
[2] | Collateral amounted to $101,001,407 on open futures contracts.

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