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FINANCIAL HIGHLIGHTS (Details) - $ / shares | 12 Months Ended
--- | ---
Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Per Share Operating Performance: |  |  |
Net asset value, beginning of year | $ 35.23 | $ 35.45 | $ 27.81
Total income (loss) | 3.17 | 0.06 | 7.95
Total expenses | (0.39) | (0.28) | (0.31)
Net increase (decrease) in net asset value | 2.78 | (0.22) | 7.64
Net asset value, end of year | $ 38.01 | $ 35.23 | $ 35.45
Total Return | 7.89% | (0.62%) | 27.47%
Ratios to Average Net Assets |  |  |
Total income (loss) | 9.39% | 0.72% | 31.17%
Management fees | 0.60% | 0.60% | 0.60%
Total expenses excluding management fees | 0.42% | 0.19% | 0.25%
Net income (loss) | 8.36% | (0.07%) | 30.32%

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