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CONTRACTS AND AGREEMENTS (Brokerage Commissions) (Details) - USD ($) | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2016 | Sep. 30, 2015 | Sep. 30, 2016 | Sep. 30, 2015
Long Duration Contracts Assumptions By Product And Guarantee [Line Items] |  |  |  |
Brokerage commissions | $ 4,869 | $ 5,205 | $ 17,285 | $ 15,370
Brokerage commissions as a percentage of average daily net assets | 0.02% | 0.03% | 0.02% | 0.03%
Rebalancing Investments Transaction [Member] |  |  |  |
Long Duration Contracts Assumptions By Product And Guarantee [Line Items] |  |  |  |
Brokerage commissions |  |  | $ 13,033 | $ 9,525
Brokerage commissions as a percentage of average daily net assets | 75.40% | 61.97% | 75.40% | 61.97%
Trades Necessitated By Creation And Redemption Activity [Member] |  |  |  |
Long Duration Contracts Assumptions By Product And Guarantee [Line Items] |  |  |  |
Brokerage commissions |  |  | $ 4,252 | $ 5,845
Brokerage commissions as a percentage of average daily net assets | 24.60% | 38.03% | 24.60% | 38.03%

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