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CONTRACTS AND AGREEMENTS - Brokerage and Futures Commissions (Details) - USD ($) | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2019 | Sep. 30, 2018 | Sep. 30, 2019 | Sep. 30, 2018
Total commissions accrued to brokers | $ 312 | $ 434 | $ 948 | $ 1,219
Total commissions as annualized percentage of average total net assets | 0.03% | 0.02% | 0.03% | 0.02%
Rebalancing Investments Transaction [Member] |  |  |  |
Total commissions accrued to brokers |  |  | $ 850 | $ 909
Total commissions as annualized percentage of average total net assets | 89.66% | 74.57% | 89.66% | 74.57%
Creation And Redemption Activity [Member] |  |  |  |
Total commissions accrued to brokers |  |  | $ 98 | $ 310
Total commissions as annualized percentage of average total net assets | 10.34% | 25.43% | 10.34% | 25.43%

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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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