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CONTRACTS AND AGREEMENTS (Brokerage Commission) (Details) - USD ($) | 12 Months Ended
--- | ---
Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Commissions accrued to brokers | $ 1,728,440 | $ 2,000,888 | $ 2,371,433
Percentage of commissions accrued | 0.35% | 0.37% | 0.39%
Rebalancing Investments Transaction [Member] |  |  |
Commissions accrued to brokers | $ 1,420,519 | $ 1,872,019 | $ 2,089,974
Percentage of commissions accrued | 82.19% | 93.56% | 88.13%
Creation And Redemption Activity [Member] |  |  |
Commissions accrued to brokers | $ 307,921 | $ 128,869 | $ 281,459
Percentage of commissions accrued | 17.81% | 6.44% | 11.87%

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- Definition The amount of expense during the period for floor brokerage fees paid to other broker-dealers to execute trades on their behalf, stock exchange fees, order flow fees, and clearance fees. + References No definition available. + Details
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- Details
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