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Schedule of Investments (Parenthetical) - USD ($) | 12 Months Ended
--- | ---
Dec. 31, 2015 | Dec. 31, 2014
Collateral Amount On Open Futures Contracts | $ 29,320,958 | $ 19,785,491
US Treasury Securities | Cash Equivalents | U.S.Treasury Bills 0.13%, 1/21/2016 |  |
Interest rate | 0.13% |
Expiration date | 1/21/2016 |
US Treasury Securities | Cash Equivalents | U.S.Treasury Bills 0.15%, 1/28/2016 |  |
Interest rate | 0.15% |
Expiration date | 1/28/2016 |
US Treasury Securities | Cash Equivalents | U.S.Treasury Bills 0.19%, 2/04/2016 |  |
Interest rate | 0.19% |
Expiration date | 2/04/2016 |
US Treasury Securities | Cash Equivalents | U.S.Treasury Bills 0.22%, 2/11/2016 |  |
Interest rate | 0.22% |
Expiration date | 2/11/2016 |
US Treasury Securities | Cash Equivalents | U.S.Treasury Bills 0.20%, 2/18/2016 |  |
Interest rate | 0.20% |
Expiration date | 2/18/2016 |
US Treasury Securities | Cash Equivalents | U.S.Treasury Bills 0.20%, 2/25/2016 |  |
Interest rate | 0.20% |
Expiration date | 2/25/2016 |
US Treasury Securities | Cash Equivalents | U.S.Treasury Bills 0.23%, 3/03/2016 |  |
Interest rate | 0.23% |
Expiration date | 3/03/2016 |
US Treasury Securities | Cash Equivalents | U.S.Treasury Bills 0.26%, 3/10/2016 |  |
Interest rate | 0.26% |
Expiration date | 3/10/2016 |
US Treasury Securities | Cash Equivalents | U.S.Treasury Bills 0.24%, 3/17/2016 |  |
Interest rate | 0.24% |
Expiration date | 3/17/2016 |
US Treasury Securities | Cash Equivalents | U.S.Treasury Bills 0.09%, 3/24/2016 |  |
Interest rate | 0.09% |
Expiration date | 3/24/2016 |
US Treasury Securities | Cash Equivalents | U.S.Treasury Bills 0.07%, 3/31/2016 |  |
Interest rate | 0.07% |
Expiration date | 3/31/2016 |
US Treasury Securities | Cash Equivalents | U.S.Treasury Bills 0.07%, 4/07/2016 |  |
Interest rate | 0.07% |
Expiration date | 4/07/2016 |
US Treasury Securities | Cash Equivalents | U.S.Treasury Bills 0.07%, 4/14/2016 |  |
Interest rate | 0.07% |
Expiration date | 4/14/2016 |
US Treasury Securities | Cash Equivalents | U.S.Treasury Bills 0.11%, 4/21/2016 |  |
Interest rate | 0.11% |
Expiration date | 4/21/2016 |
US Treasury Securities | Cash Equivalents | U.S.Treasury Bills 0.21%, 4/28/2016 |  |
Interest rate | 0.21% |
Expiration date | 4/28/2016 |
US Treasury Securities | Cash Equivalents | U.S.Treasury Bills 0.26%, 5/05/2016 |  |
Interest rate | 0.26% |
Expiration date | 5/05/2016 |
US Treasury Securities | Cash Equivalents | U.S.Treasury Bills 0.33%, 5/12/2016 |  |
Interest rate | 0.33% |
Expiration date | 5/12/2016 |
US Treasury Securities | Cash Equivalents | U.S.Treasury Bills 0.31%, 5/19/2016 |  |
Interest rate | 0.31% |
Expiration date | 5/19/2016 |
US Treasury Securities | Cash Equivalents | U.S.Treasury Bills 0.35%, 5/26/2016 |  |
Interest rate | 0.35% |
Expiration date | 5/26/2016 |
US Treasury Securities | Cash Equivalents | U.S.Treasury Bills 0.43%, 6/02/2016 |  |
Interest rate | 0.43% |
Expiration date | 6/02/2016 |
US Treasury Securities | Cash Equivalents | U.S.Treasury Bills 0.52%, 6/09/2016 |  |
Interest rate | 0.52% |
Expiration date | 6/09/2016 |
US Treasury Securities | Cash Equivalents | U.S.Treasury Bills 0.48%, 6/16/2016 |  |
Interest rate | 0.48% |
Expiration date | 6/16/2016 |
US Treasury Securities | Cash Equivalents | U.S.Treasury Bills 0.46%, 6/23/2016 |  |
Interest rate | 0.46% |
Expiration date | 6/23/2016 |
US Treasury Securities | Cash Equivalents | U.S.Treasury Bills 0.47%, 6/30/2016 |  |
Interest rate | 0.47% |
Expiration date | 6/30/2016 |
U.S. Treasury Bill, 0.05%, 1/15/2015 | US Treasury Securities | Cash Equivalents |  |
Interest rate |  | 0.05%
Expiration date |  | 1/15/2015
U.S. Treasury Bill 0.10%, 6/25/2015 | US Treasury Securities | Cash Equivalents |  |
Interest rate |  | 0.10%
Expiration date |  | 6/25/2015
United States | NYMEX WTI Crude Oil Futures CL February 2015 contracts, expiring January 2015 | Open Futures Contracts, Long |  |
Expiration date |  | January 2015
United States | NYMEX WTI Crude Oil Futures CL March 2015 contracts, expiring February 2015 | Open Futures Contracts, Long |  |
Expiration date |  | February 2015
United States | NYMEX WTI Crude Oil Futures CL April 2015 contracts, expiring March 2015 | Open Futures Contracts, Long |  |
Expiration date |  | March 2015
United States | NYMEX WTI Crude Oil Futures CL May 2015 contracts, expiring April 2015 | Open Futures Contracts, Long |  |
Expiration date |  | April 2015
United States | NYMEX WTI Crude Oil Futures CL June 2015 contracts, expiring May 2015 | Open Futures Contracts, Long |  |
Expiration date |  | May 2015
United States | NYMEX WTI Crude Oil Futures CL July 2015 contracts, expiring June 2015 | Open Futures Contracts, Long |  |
Expiration date |  | June 2015
United States | NYMEX WTI Crude Oil Futures CL August 2015 contracts, expiring July 2015 | Open Futures Contracts, Long |  |
Expiration date |  | July 2015
United States | NYMEX WTI Crude Oil Futures CL September 2015 contracts, expiring August 2015 | Open Futures Contracts, Long |  |
Expiration date |  | August 2015
United States | NYMEX WTI Crude Oil Futures CL October 2015 contracts, expiring September 2015 | Open Futures Contracts, Long |  |
Expiration date |  | September 2015
United States | NYMEX WTI Crude Oil Futures CL November 2015 contracts, expiring October 2015 | Open Futures Contracts, Long |  |
Expiration date |  | October 2015
United States | NYMEX WTI Crude Oil Futures CL December 2015 contracts, expiring November 2015 | Open Futures Contracts, Long |  |
Expiration date |  | November 2015
United States | NYMEX WTI Crude Oil Futures CL January 2016 contracts, expiring December 2015 | Open Futures Contracts, Long |  |
Expiration date |  | December 2015
United States | NYMEX WTI Crude Oil Futures CL February 2016 contracts, expiring January 2016 | Open Futures Contracts, Long |  |
Expiration date | January 2016 |
United States | NYMEX WTI Crude Oil Futures CL March 2016 contracts, expiring February 2016 | Open Futures Contracts, Long |  |
Expiration date | February 2016 |
United States | NYMEX WTI Crude Oil Futures CL April 2016 contracts, expiring March 2016 | Open Futures Contracts, Long |  |
Expiration date | March 2016 |
United States | NYMEX WTI Crude Oil Futures CL May 2016 contracts, expiring April 2016 | Open Futures Contracts, Long |  |
Expiration date | April 2016 |
United States | NYMEX WTI Crude Oil Futures CL June 2016 contracts, expiring May 2016 | Open Futures Contracts, Long |  |
Expiration date | May 2016 |
United States | NYMEX WTI Crude Oil Futures CL July 2016 contracts, expiring June 2016 | Open Futures Contracts, Long |  |
Expiration date | June 2016 |
United States | NYMEX WTI Crude Oil Futures CL August 2016 contracts, expiring July 2016 | Open Futures Contracts, Long |  |
Expiration date | July 2016 |
United States | NYMEX WTI Crude Oil Futures CL September 2016 contracts, expiring August 2016 | Open Futures Contracts, Long |  |
Expiration date | August 2016 |
United States | NYMEX WTI Crude Oil Futures CL October 2016 contracts, expiring September 2016 | Open Futures Contracts, Long |  |
Expiration date | September 2016 |
United States | NYMEX WTI Crude Oil Futures CL November 2016 contracts, expiring October 2016 | Open Futures Contracts, Long |  |
Expiration date | October 2016 |
United States | NYMEX WTI Crude Oil Futures CL December 2016 contracts, expiring November 2016 | Open Futures Contracts, Long |  |
Expiration date | November 2016 |
United States | NYMEX WTI Crude Oil Futures CL January 2017 contracts, expiring December 2016 | Open Futures Contracts, Long |  |
Expiration date | December 2016 |

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