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CONTRACTS AND AGREEMENTS - Brokerage and Futures Commissions (Details) - USD ($) | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2019 | Jun. 30, 2018 | Jun. 30, 2019 | Jun. 30, 2018
Total commissions accrued to brokers | $ 264 | $ 467 | $ 636 | $ 785
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 |  |  | $ 538 | $ 565
Total commissions as annualized percentage of average total net assets | 84.59% | 71.97% | 84.59% | 71.97%
Creation And Redemption Activity [Member] |  |  |  |
Total commissions accrued to brokers |  |  | $ 98 | $ 220
Total commissions as annualized percentage of average total net assets | 15.41% | 28.03% | 15.41% | 28.03%

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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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