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Condensed Schedule of Investments (Parenthetical) | 9 Months Ended
--- | ---
Sep. 30, 2018 USD ($)
Collateral Amount On Open Futures Contracts | $ 19,957,672
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 1.97%, 10/18/2018 [Member] |
Interest rate | 1.97%
Expiration date | 10/18/2018
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.00%, 10/25/2018 [Member] |
Interest rate | 2.00%
Expiration date | 10/25/2018
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.00%, 11/01/2018 [Member] |
Interest rate | 2.00%
Expiration date | 11/01/2018
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.03%, 11/08/2018 [Member] |
Interest rate | 2.03%
Expiration date | 11/08/2018
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.05%, 11/15/2018 [Member] |
Interest rate | 2.05%
Expiration date | 11/15/2018
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.07%, 11/23/2018 [Member] |
Interest rate | 2.07%
Expiration date | 11/23/2018
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.05%, 11/29/2018 [Member] |
Interest rate | 2.05%
Expiration date | 11/29/2018
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.09%, 12/06/2018 [Member] |
Interest rate | 2.09%
Expiration date | 12/06/2018
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.06%, 12/13/2018 [Member] |
Interest rate | 2.06%
Expiration date | 12/13/2018
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.09%, 12/20/2018 [Member] |
Interest rate | 2.09%
Expiration date | 12/20/2018
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.07%, 12/27/2018 [Member] |
Interest rate | 2.07%
Expiration date | 12/27/2018
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.10%, 1/03/2019 [Member] |
Interest rate | 2.10%
Expiration date | 1/03/2019
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.10%, 1/10/2019 [Member] |
Interest rate | 2.10%
Expiration date | 1/10/2019
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.13%, 1/17/2019 [Member] |
Interest rate | 2.13%
Expiration date | 1/17/2019
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.15%, 1/24/2019 [Member] |
Interest rate | 2.15%
Expiration date | 1/24/2019
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.18%, 1/31/2019 [Member] |
Interest rate | 2.18%
Expiration date | 1/31/2019
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.20%, 2/07/2019 [Member] |
Interest rate | 2.20%
Expiration date | 2/07/2019
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.20%, 2/21/2019 [Member] |
Interest rate | 2.20%
Expiration date | 2/21/2019
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.38%, 3/07/2019 [Member] |
Interest rate | 2.38%
Expiration date | 3/07/2019
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.28%, 3/14/2019 [Member] |
Interest rate | 2.28%
Expiration date | 3/14/2019
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.33%, 3/21/2019 [Member] |
Interest rate | 2.33%
Expiration date | 3/21/2019
Cash Equivalents [Member] | United States Treasury Obligations [Member] | U.S. Treasury Bills 2.34%, 3/28/2019 [Member] |
Interest rate | 2.34%
Expiration date | 3/28/2019

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