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Schedule of Investments (Parenthetical) - USD ($) | 12 Months Ended
--- | ---
Dec. 31, 2017 | Dec. 31, 2016
Collateral Amount On Open Futures Contracts | $ 4,988,459 | $ 6,997,275
United States | US Treasury Securities | Cash Equivalents | U.S.Treasury Bills 0.43%, 3/30/2017 |  |
Interest rate |  | 0.43%
Expiration date |  | 3/30/2017
United States | U.S.Treasury Bills 1.12%, 1/04/2018 | US Treasury Securities | Cash Equivalents |  |
Interest rate | 1.12% |
Expiration date | 1/04/2018 |
United States | U.S.Treasury Bills 1.11%, 1/11/2018 | US Treasury Securities | Cash Equivalents |  |
Interest rate | 1.11% |
Expiration date | 1/11/2018 |
United States | U.S.Treasury Bills 1.10%, 1/18/2018 | US Treasury Securities | Cash Equivalents |  |
Interest rate | 1.10% |
Expiration date | 1/18/2018 |
United States | U.S.Treasury Bills 1.12%, 1/25/2018 | US Treasury Securities | Cash Equivalents |  |
Interest rate | 1.12% |
Expiration date | 1/25/2018 |
United States | U.S.Treasury Bills 1.12%, 2/01/2018 | US Treasury Securities | Cash Equivalents |  |
Interest rate | 1.12% |
Expiration date | 2/01/2018 |
United States | U.S.Treasury Bills 1.13%, 2/08/2018 | US Treasury Securities | Cash Equivalents |  |
Interest rate | 1.13% |
Expiration date | 2/08/2018 |
United States | U.S.Treasury Bills 1.12%, 2/15/2018 | US Treasury Securities | Cash Equivalents |  |
Interest rate | 1.12% |
Expiration date | 2/15/2018 |
United States | U.S.Treasury Bills 1.10%, 2/22/2018 | US Treasury Securities | Cash Equivalents |  |
Interest rate | 1.10% |
Expiration date | 2/22/2018 |
United States | U.S.Treasury Bills 1.09%, 3/01/2018 | US Treasury Securities | Cash Equivalents |  |
Interest rate | 1.09% |
Expiration date | 3/01/2018 |
United States | U.S.Treasury Bills 1.14%, 3/08/2018 | US Treasury Securities | Cash Equivalents |  |
Interest rate | 1.14% |
Expiration date | 3/08/2018 |
United States | U.S.Treasury Bills 1.14%, 3/15/2018 | US Treasury Securities | Cash Equivalents |  |
Interest rate | 1.14% |
Expiration date | 3/15/2018 |
United States | U.S.Treasury Bills 1.16%, 3/22/2018 | US Treasury Securities | Cash Equivalents |  |
Interest rate | 1.16% |
Expiration date | 3/22/2018 |
United States | U.S.Treasury Bills 1.17%, 3/29/2018 | US Treasury Securities | Cash Equivalents |  |
Interest rate | 1.17% |
Expiration date | 3/29/2018 |
United States | U.S.Treasury Bills 1.19%, 4/05/2018 | US Treasury Securities | Cash Equivalents |  |
Interest rate | 1.19% |
Expiration date | 4/05/2018 |
United States | U.S.Treasury Bills 1.22%, 4/12/2018 | US Treasury Securities | Cash Equivalents |  |
Interest rate | 1.22% |
Expiration date | 4/12/2018 |
United States | U.S.Treasury Bills 1.23%, 4/19/2018 | US Treasury Securities | Cash Equivalents |  |
Interest rate | 1.23% |
Expiration date | 4/19/2018 |
United States | U.S.Treasury Bills 1.25%, 4/26/2018 | US Treasury Securities | Cash Equivalents |  |
Interest rate | 1.25% |
Expiration date | 4/26/2018 |
United States | U.S.Treasury Bills 1.27%, 5/03/2018 | US Treasury Securities | Cash Equivalents |  |
Interest rate | 1.27% |
Expiration date | 5/03/2018 |
United States | U.S.Treasury Bills 1.32%, 5/10/2018 | US Treasury Securities | Cash Equivalents |  |
Interest rate | 1.32% |
Expiration date | 5/10/2018 |
United States | U.S.Treasury Bills 1.37%, 5/17/2018 | US Treasury Securities | Cash Equivalents |  |
Interest rate | 1.37% |
Expiration date | 5/17/2018 |
United States | U.S.Treasury Bills 1.43%, 5/24/2018 | US Treasury Securities | Cash Equivalents |  |
Interest rate | 1.43% |
Expiration date | 5/24/2018 |
United States | U.S.Treasury Bills 1.43%, 5/31/2018 | US Treasury Securities | Cash Equivalents |  |
Interest rate | 1.43% |
Expiration date | 5/31/2018 |
United States | U.S.Treasury Bills 1.45%, 6/07/2018 | US Treasury Securities | Cash Equivalents |  |
Interest rate | 1.45% |
Expiration date | 6/07/2018 |
United States | U.S.Treasury Bills 1.46%, 6/14/2018 | US Treasury Securities | Cash Equivalents |  |
Interest rate | 1.46% |
Expiration date | 6/14/2018 |
United States | U.S.Treasury Bills 1.49%, 6/21/2018 | US Treasury Securities | Cash Equivalents |  |
Interest rate | 1.49% |
Expiration date | 6/21/2018 |
United States | U.S.Treasury Bills 1.50%, 6/28/2018 | US Treasury Securities | Cash Equivalents |  |
Interest rate | 1.50% |
Expiration date | 6/28/2018 |
United States | Us Treasury Bills 0.43%, 1/19/2017 | US Treasury Securities | Cash Equivalents |  |
Interest rate |  | 0.43%
Expiration date |  | 1/19/2017
United States | Us Treasury Bills 0.34%, 1/05/2017 | US Treasury Securities | Cash Equivalents |  |
Interest rate |  | 0.34%
Expiration date |  | 1/05/2017
United States | Us Treasury Bills 0.36%, 1/26/2017 | US Treasury Securities | Cash Equivalents |  |
Interest rate |  | 0.36%
Expiration date |  | 1/26/2017
United States | Us Treasury Bills 0.40%, 2/02/2017 | US Treasury Securities | Cash Equivalents |  |
Interest rate |  | 0.40%
Expiration date |  | 2/02/2017
United States | Us Treasury Bills 0.42%, 2/09/2017 | US Treasury Securities | Cash Equivalents |  |
Interest rate |  | 0.42%
Expiration date |  | 2/09/2017
United States | Us Treasury Bills 0.45%, 2/16/2017 | US Treasury Securities | Cash Equivalents |  |
Interest rate |  | 0.45%
Expiration date |  | 2/16/2017
United States | Us Treasury Bills 0.45%, 2/23/2017 | US Treasury Securities | Cash Equivalents |  |
Interest rate |  | 0.45%
Expiration date |  | 2/23/2017
United States | Us Treasury Bills 0.45%, 3/02/2017 | US Treasury Securities | Cash Equivalents |  |
Interest rate |  | 0.45%
Expiration date |  | 3/02/2017
United States | Us Treasury Bills 0.47%, 3/09/2017 | US Treasury Securities | Cash Equivalents |  |
Interest rate |  | 0.47%
Expiration date |  | 3/09/2017
United States | Us Treasury Bills 0.50%, 3/16/2017 | US Treasury Securities | Cash Equivalents |  |
Interest rate |  | 0.50%
Expiration date |  | 3/16/2017
United States | Us Treasury Bills 0.45%, 3/23/2017 | US Treasury Securities | Cash Equivalents |  |
Interest rate |  | 0.45%
Expiration date |  | 3/23/2017
United States | US Treasury Bills 0.46%, 4/06/2017 | US Treasury Securities | Cash Equivalents |  |
Interest rate |  | 0.46%
Expiration date |  | 4/06/2017
United States | US Treasury Bills 0.47%, 4/13/2017 | US Treasury Securities | Cash Equivalents |  |
Interest rate |  | 0.47%
Expiration date |  | 4/13/2017
United States | US Treasury Bills 0.46%, 4/20/2017 | US Treasury Securities | Cash Equivalents |  |
Interest rate |  | 0.46%
Expiration date |  | 4/20/2017
United States | US Treasury Bills 0.47%, 4/27/2017 | US Treasury Securities | Cash Equivalents |  |
Interest rate |  | 0.47%
Expiration date |  | 4/27/2017
United States | US Treasury Bills 0.49%, 5/04/2017 | US Treasury Securities | Cash Equivalents |  |
Interest rate |  | 0.49%
Expiration date |  | 5/04/2017
United States | US Treasury Bills 0.55%, 5/11/2017 | US Treasury Securities | Cash Equivalents |  |
Interest rate |  | 0.55%
Expiration date |  | 5/11/2017
United States | US Treasury Bills 0.60%, 5/18/2017 | US Treasury Securities | Cash Equivalents |  |
Interest rate |  | 0.60%
Expiration date |  | 5/18/2017
United States | US Treasury Bills 0.61%, 5/25/2017 | US Treasury Securities | Cash Equivalents |  |
Interest rate |  | 0.61%
Expiration date |  | 5/25/2017
United States | US Treasury Bills 0.60%, 6/01/2017 | US Treasury Securities | Cash Equivalents |  |
Interest rate |  | 0.60%
Expiration date |  | 6/01/2017
United States | US Treasury Bills 0.62%, 6/08/2017 | US Treasury Securities | Cash Equivalents |  |
Interest rate |  | 0.62%
Expiration date |  | 6/08/2017
United States | US Treasury Bills 0.65%, 6/15/2017 | US Treasury Securities | Cash Equivalents |  |
Interest rate |  | 0.65%
Expiration date |  | 6/15/2017
United States | US Treasury Bills 0.64%, 6/22/2017 | US Treasury Securities | Cash Equivalents |  |
Interest rate |  | 0.64%
Expiration date |  | 6/22/2017
United States | US Treasury Bills 0.60%, 6/29/2017 | US Treasury Securities | Cash Equivalents |  |
Interest rate |  | 0.60%
Expiration date |  | 6/29/2017

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