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Condensed Schedule of Investments | Jun. 30, 2017 USD ($) Number
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Unrealized Gain (Loss) on Open Commodity Contracts | $ 5,291,350 |
Open Futures Contracts, Long [Member] | United States [Member] | ICE Natural Gas Futures LD1 H August 2017 contracts, expiring August 2017 [Member] |  |
Number of Contracts | Number | 20,000 |
Unrealized Gain (Loss) on Open Commodity Contracts | $ 1,078,750 |
% of Partners' Capital | 0.24% |
Open Futures Contracts, Long [Member] | United States [Member] | NYMEX Natural Gas Futures NG August 2017 contracts, expiring July 2017 [Member] |  |
Number of Contracts | Number | 9,745 |
Unrealized Gain (Loss) on Open Commodity Contracts | $ 4,212,600 |
% of Partners' Capital | 0.94% |
Total Open Futures Contracts [Member] | Open Futures Contracts, Long [Member] | United States [Member] |  |
Number of Contracts | Number | 29,745 | [1]
Unrealized Gain (Loss) on Open Commodity Contracts | $ 5,291,350 | [1]
% of Partners' Capital | 1.18% | [1]
Cash Equivalents [Member] | United States [Member] |  |
Market Value | $ 373,959,761 |
% of Partners' Capital | 83.57% |
Cash Equivalents [Member] | United States [Member] | US Treasury Securities [Member] |  |
Market Value | $ 353,959,761 |
% of Partners' Capital | 79.11% |
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 | $ 9,999,146 |
% of Partners' Capital | 2.23% |
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 | $ 14,997,075 |
% of Partners' Capital | 3.35% |
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 | $ 9,996,807 |
% of Partners' Capital | 2.23% |
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 | $ 4,997,851 |
% of Partners' Capital | 1.12% |
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 | $ 9,993,222 |
% of Partners' Capital | 2.23% |
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 | $ 9,991,514 |
% of Partners' Capital | 2.23% |
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 | $ 14,984,925 |
% of Partners' Capital | 3.35% |
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 | $ 14,980,810 |
% of Partners' Capital | 3.35% |
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 | $ 9,984,133 |
% of Partners' Capital | 2.23% |
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 | $ 9,980,183 |
% of Partners' Capital | 2.23% |
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 | $ 14,966,996 |
% of Partners' Capital | 3.35% |
Cash Equivalents [Member] | United States [Member] | US Treasury Securities [Member] | U.S. Treasury Bills 0.90%, 10/05/2017 [Member] |  |
Principal Amount | $ 15,000,000 |
Market Value | $ 14,964,200 |
% of Partners' Capital | 3.34% |
Cash Equivalents [Member] | United States [Member] | US Treasury Securities [Member] | U.S. Treasury Bills 0.92%, 10/12/2017 [Member] |  |
Principal Amount | $ 20,000,000 |
Market Value | $ 19,947,642 |
% of Partners' Capital | 4.46% |
Cash Equivalents [Member] | United States [Member] | US Treasury Securities [Member] | U.S. Treasury Bills 0.91%, 10/19/2017 [Member] |  |
Principal Amount | $ 20,000,000 |
Market Value | $ 19,944,694 |
% of Partners' Capital | 4.46% |
Cash Equivalents [Member] | United States [Member] | US Treasury Securities [Member] | U.S. Treasury Bills 0.95%, 10/26/2017 [Member] |  |
Principal Amount | $ 10,000,000 |
Market Value | $ 9,969,125 |
% of Partners' Capital | 2.23% |
Cash Equivalents [Member] | United States [Member] | US Treasury Securities [Member] | U.S. Treasury Bills 0.97%, 11/02/2017 [Member] |  |
Principal Amount | $ 15,000,000 |
Market Value | $ 14,950,142 |
% of Partners' Capital | 3.34% |
Cash Equivalents [Member] | United States [Member] | US Treasury Securities [Member] | U.S. Treasury Bills 1.01%, 11/09/2017 [Member] |  |
Principal Amount | $ 15,000,000 |
Market Value | $ 14,945,144 |
% of Partners' Capital | 3.34% |
Cash Equivalents [Member] | United States [Member] | US Treasury Securities [Member] | U.S. Treasury Bills 0.98%, 11/16/2017 [Member] |  |
Principal Amount | $ 20,000,000 |
Market Value | $ 19,924,867 |
% of Partners' Capital | 4.45% |
Cash Equivalents [Member] | United States [Member] | US Treasury Securities [Member] | U.S. Treasury Bills 1.05%, 11/24/2017 [Member] |  |
Principal Amount | $ 20,000,000 |
Market Value | $ 19,915,239 |
% of Partners' Capital | 4.45% |
Cash Equivalents [Member] | United States [Member] | US Treasury Securities [Member] | U.S. Treasury Bills 1.05%, 11/30/2017 [Member] |  |
Principal Amount | $ 20,000,000 |
Market Value | $ 19,911,755 |
% of Partners' Capital | 4.45% |
Cash Equivalents [Member] | United States [Member] | US Treasury Securities [Member] | U.S. Treasury Bills 1.08%, 12/07/2017 [Member] |  |
Principal Amount | $ 15,000,000 |
Market Value | $ 14,929,113 |
% of Partners' Capital | 3.34% |
Cash Equivalents [Member] | United States [Member] | US Treasury Securities [Member] | U.S. Treasury Bills 1.09%, 12/14/2017 [Member] |  |
Principal Amount | $ 20,000,000 |
Market Value | $ 19,900,400 |
% of Partners' Capital | 4.45% |
Cash Equivalents [Member] | United States [Member] | US Treasury Securities [Member] | U.S. Treasury Bills 1.11%, 12/21/2017 [Member] |  |
Principal Amount | $ 20,000,000 |
Market Value | $ 19,894,278 |
% of Partners' Capital | 4.45% |
Cash Equivalents [Member] | United States [Member] | US Treasury Securities [Member] | U.S. Treasury Bills 1.10%, 12/28/2017 [Member] |  |
Principal Amount | $ 20,000,000 |
Market Value | $ 19,890,500 |
% of Partners' Capital | 4.45% |
Cash Equivalents [Member] | United States [Member] | Money Market Funds [Member] |  |
Market Value | $ 20,000,000 |
% of Partners' Capital | 4.46% |
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 | 2.23% |
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 | 2.23% |
[1] | Collateral amounted to $48,122,106 on open futures contracts.

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