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CONTRACTS AND AGREEMENTS (Brokerage Commission) (Details) - USD ($) | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2017 | Sep. 30, 2016 | Sep. 30, 2017 | Sep. 30, 2016
Floor Brokerage Exchange and Clearance Fees | $ 403,584 | $ 440,975 | $ 1,204,240 | $ 1,526,497
Percentage Of Average Daily Net Assets | 0.34% | 0.39% | 0.34% | 0.39%
Rebalancing Investments Transaction [Member] |  |  |  |
Floor Brokerage Exchange and Clearance Fees |  |  | $ 998,598 | $ 1,444,429
Percentage Of Average Daily Net Assets | 82.92% | 94.62% | 82.92% | 94.62%
Creation And Redemption Activity [Member] |  |  |  |
Floor Brokerage Exchange and Clearance Fees |  |  | $ 205,642 | $ 82,068
Percentage Of Average Daily Net Assets | 17.08% | 5.38% | 17.08% | 5.38%

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