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FINANCIAL HIGHLIGHTS (Tables) | 9 Months Ended
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Sep. 30, 2025
FINANCIAL HIGHLIGHTS |
Schedule of per share performance data and other supplemental financial data | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | Three months ended | ​ | Three months ended | ​ | Nine months ended |  | Nine months ended | ​
​ | ​ | September 30, 2025 | ​ | September 30, 2024 | ​ | September 30, 2025 | ​ | September 30, 2024 | ​
​ |  | (Unaudited) |  | (Unaudited) | ​ | (Unaudited) |  | (Unaudited) | ​
Per Share Operating Performance: |  | ​ |  |  | ​ |  | ​ | ​ |  |  | ​ |  | ​
Net asset value, beginning of period | ​ | $ | 35.19 | ​ | $ | 40.54 | ​ | $ | 38.01 | ​ | $ | 35.23 | ​
Total income (loss) | ​ |  | 0.41 | ​ |  | (4.51) | ​ |  | (2.23) | ​ |  | 0.97 | ​
Total expenses | ​ |  | (0.10) | ​ |  | (0.12) | ​ |  | (0.28) | ​ |  | (0.29) | ​
Net increase (decrease) in net asset value | ​ |  | 0.31 | ​ |  | (4.63) | ​ |  | (2.51) | ​ |  | 0.68 | ​
Net asset value, end of period | ​ | $ | 35.50 | ​ | $ | 35.91 | ​ | $ | 35.50 | ​ | $ | 35.91 | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Total Return | ​ |  | 0.88 | % |  | (11.42) | % |  | (6.60) | % |  | 1.93 | %
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Ratios to Average Net Assets | ​ |  | ​ | ​ |  |  | ​ |  |  | ​ |  |  | ​
Total income (loss) | ​ |  | 1.15 | % |  | (11.79) | % |  | (6.64) | % |  | 4.13 | %
Management fees# | ​ |  | 0.60 | % |  | 0.60 | % |  | 0.60 | % |  | 0.60 | %
Total expenses excluding management fees# | ​ |  | 0.53 | % |  | 0.63 | % |  | 0.42 | % |  | 0.40 | %
Net income (loss) | ​ |  | 0.87 | % |  | (12.10) | % |  | (7.41) | % |  | 3.38 | %
# | Annualized.

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- Definition Tabular disclosure of per unit performance data and other supplemental financial data. + References No definition available. + Details
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