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Condensed Schedule of Investments | Mar. 31, 2017 USD ($) Number
--- | ---
Unrealized Gain (Loss) on Open Commodity Contracts | $ 22,140,010 |
Open Futures Contracts, Long [Member] | United States [Member] | ICE Natural Gas Futures LD1 H May 2017 contracts, expiring May 2017 |  |
Number of Contracts | Number | 20,000 |
Unrealized Gain (Loss) on Open Commodity Contracts | $ 8,115,000 |
% of Partners' Capital | 1.76% |
Open Futures Contracts, Long [Member] | United States [Member] | NYMEX Natural Gas Futures NG May 2017 contracts, expiring April 2017 |  |
Number of Contracts | Number | 9,442 |
Unrealized Gain (Loss) on Open Commodity Contracts | $ 14,025,010 |
% of Partners' Capital | 3.05% |
Total Open Futures Contracts [Member] | Open Futures Contracts, Long [Member] | United States [Member] |  |
Number of Contracts | Number | 29,442 | [1]
Unrealized Gain (Loss) on Open Commodity Contracts | $ 22,140,010 | [1]
% of Partners' Capital | 4.81% | [1]
Cash Equivalents [Member] | United States [Member] |  |
Market Value | $ 424,441,352 |
% of Partners' Capital | 92.13% |
Cash Equivalents [Member] | United States [Member] | US Treasury Securities [Member] |  |
Market Value | $ 404,441,352 |
% of Partners' Capital | 87.79% |
Cash Equivalents [Member] | United States [Member] | US Treasury Securities [Member] | U.S. Treasury Bills 0.46%, 4/06/2017 [Member] |  |
Principal Amount | $ 20,000,000 |
Market Value | $ 19,998,736 |
% of Partners' Capital | 4.34% |
Cash Equivalents [Member] | United States [Member] | US Treasury Securities [Member] | U.S. Treasury Bills 0.47%, 4/13/2017 [Member] |  |
Principal Amount | $ 25,000,000 |
Market Value | $ 24,996,083 |
% of Partners' Capital | 5.43% |
Cash Equivalents [Member] | United States [Member] | US Treasury Securities [Member] | U.S. Treasury Bills 0.46%, 4/20/2017 [Member] |  |
Principal Amount | $ 25,000,000 |
Market Value | $ 24,993,997 |
% of Partners' Capital | 5.42% |
Cash Equivalents [Member] | United States [Member] | US Treasury Securities [Member] | U.S. Treasury Bills 0.47%, 4/27/2017 [Member] |  |
Principal Amount | $ 25,000,000 |
Market Value | $ 24,991,604 |
% of Partners' Capital | 5.42% |
Cash Equivalents [Member] | United States [Member] | US Treasury Securities [Member] | U.S. Treasury Bills 0.49%, 5/04/2017 [Member] |  |
Principal Amount | $ 20,000,000 |
Market Value | $ 19,990,971 |
% of Partners' Capital | 4.34% |
Cash Equivalents [Member] | United States [Member] | US Treasury Securities [Member] | U.S. Treasury Bills 0.55%, 5/11/2017 [Member] |  |
Principal Amount | $ 20,000,000 |
Market Value | $ 19,987,889 |
% of Partners' Capital | 4.34% |
Cash Equivalents [Member] | United States [Member] | US Treasury Securities [Member] | U.S. Treasury Bills 0.60%, 5/18/2017 [Member] |  |
Principal Amount | $ 20,000,000 |
Market Value | $ 19,984,464 |
% of Partners' Capital | 4.34% |
Cash Equivalents [Member] | United States [Member] | US Treasury Securities [Member] | U.S. Treasury Bills 0.61%, 5/25/2017 [Member] |  |
Principal Amount | $ 20,000,000 |
Market Value | $ 19,981,775 |
% of Partners' Capital | 4.34% |
Cash Equivalents [Member] | United States [Member] | US Treasury Securities [Member] | U.S. Treasury Bills 0.60%, 6/01/2017 [Member] |  |
Principal Amount | $ 25,000,000 |
Market Value | $ 24,974,795 |
% of Partners' Capital | 5.42% |
Cash Equivalents [Member] | United States [Member] | US Treasury Securities [Member] | U.S. Treasury Bills 0.62%, 6/08/2017 [Member] |  |
Principal Amount | $ 20,000,000 |
Market Value | $ 19,976,767 |
% of Partners' Capital | 4.34% |
Cash Equivalents [Member] | United States [Member] | US Treasury Securities [Member] | U.S. Treasury Bills 0.65%, 6/15/2017 [Member] |  |
Principal Amount | $ 25,000,000 |
Market Value | $ 24,966,406 |
% of Partners' Capital | 5.42% |
Cash Equivalents [Member] | United States [Member] | US Treasury Securities [Member] | U.S. Treasury Bills 0.64%, 6/22/2017 [Member] |  |
Principal Amount | $ 20,000,000 |
Market Value | $ 19,970,844 |
% of Partners' Capital | 4.33% |
Cash Equivalents [Member] | United States [Member] | US Treasury Securities [Member] | U.S. Treasury Bills 0.60%, 6/29/2017 [Member] |  |
Principal Amount | $ 15,000,000 |
Market Value | $ 14,977,750 |
% of Partners' Capital | 3.25% |
Cash Equivalents [Member] | United States [Member] | US Treasury Securities [Member] | U.S. Treasury Bills 0.62%, 7/06/2017 [Member] |  |
Principal Amount | $ 10,000,000 |
Market Value | $ 9,983,600 |
% of Partners' Capital | 2.17% |
Cash Equivalents [Member] | United States [Member] | US Treasury Securities [Member] | U.S. Treasury Bills 0.59%, 7/13/2017 [Member] |  |
Principal Amount | $ 15,000,000 |
Market Value | $ 14,974,894 |
% of Partners' Capital | 3.25% |
Cash Equivalents [Member] | United States [Member] | US Treasury Securities [Member] | U.S. Treasury Bills 0.61%, 7/20/2017 [Member] |  |
Principal Amount | $ 10,000,000 |
Market Value | $ 9,981,514 |
% of Partners' Capital | 2.17% |
Cash Equivalents [Member] | United States [Member] | US Treasury Securities [Member] | U.S. Treasury Bills 0.60%, 7/27/2017 [Member] |  |
Principal Amount | $ 5,000,000 |
Market Value | $ 4,990,331 |
% of Partners' Capital | 1.08% |
Cash Equivalents [Member] | United States [Member] | US Treasury Securities [Member] | U.S. Treasury Bills 0.61%, 8/10/2017 [Member] |  |
Principal Amount | $ 10,000,000 |
Market Value | $ 9,977,803 |
% of Partners' Capital | 2.17% |
Cash Equivalents [Member] | United States [Member] | US Treasury Securities [Member] | U.S. Treasury Bills 0.65%, 8/17/2017 [Member] |  |
Principal Amount | $ 10,000,000 |
Market Value | $ 9,975,083 |
% of Partners' Capital | 2.16% |
Cash Equivalents [Member] | United States [Member] | US Treasury Securities [Member] | U.S. Treasury Bills 0.67%, 8/24/2017 [Member] |  |
Principal Amount | $ 15,000,000 |
Market Value | $ 14,959,521 |
% of Partners' Capital | 3.25% |
Cash Equivalents [Member] | United States [Member] | US Treasury Securities [Member] | U.S. Treasury Bills 0.76%, 8/31/2017 [Member] |  |
Principal Amount | $ 15,000,000 |
Market Value | $ 14,952,183 |
% of Partners' Capital | 3.25% |
Cash Equivalents [Member] | United States [Member] | US Treasury Securities [Member] | U.S. Treasury Bills 0.84%, 9/07/2017 [Member] |  |
Principal Amount | $ 10,000,000 |
Market Value | $ 9,962,900 |
% of Partners' Capital | 2.16% |
Cash Equivalents [Member] | United States [Member] | US Treasury Securities [Member] | U.S. Treasury Bills 0.87%, 9/21/2017 [Member] |  |
Principal Amount | $ 10,000,000 |
Market Value | $ 9,958,192 |
% of Partners' Capital | 2.16% |
Cash Equivalents [Member] | United States [Member] | US Treasury Securities [Member] | U.S. Treasury Bills 0.89%, 9/28/2017 [Member] |  |
Principal Amount | $ 15,000,000 |
Market Value | $ 14,933,250 |
% of Partners' Capital | 3.24% |
Cash Equivalents [Member] | United States [Member] | Money Market Funds [Member] |  |
Market Value | $ 20,000,000 |
% of Partners' Capital | 4.34% |
Cash Equivalents [Member] | United States [Member] | Money Market Funds [Member] | Fidelity Investments Money Market Funds - Government Portfolio [Member] |  |
Principal Amount | $ 10,000,000 |
Market Value | $ 10,000,000 |
% of Partners' Capital | 2.17% |
Cash Equivalents [Member] | United States [Member] | 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 | 2.17% |
[1] | Collateral amounted to $44,975,772 on open futures contracts.

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