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FINANCIAL HIGHLIGHTS (Tables) | 9 Months Ended
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Sep. 30, 2020
FINANCIAL HIGHLIGHTS |
Schedule of per share performance data and other supplemental financial data | The following table presents per share performance data and other supplemental financial data for the three and nine months ended September 30, 2020 and 2019 for the shareholders. This information has been derived from information presented in the condensed financial statements. ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ |  | Three months ended |  | Three months ended |  | Nine months ended |  | Nine months ended |
​ | ​ | September 30, 2020 | ​ | September 30, 2019 | ​ | September 30, 2020 |  | September 30, 2019 |
​ | ​ | (Unaudited) | ​ | (Unaudited) | ​ | (Unaudited) | ​ | (Unaudited) | ​
Per Share Operating Performance: |  | ​ |  |  | ​ |  |  | ​ |  | ​ | ​ |  | ​
Net asset value, beginning of period | ​ | $ | 10.25 | ​ | $ | 19.83 | ​ | $ | 16.91 | ​ | $ | 24.35 | ​
Total income (loss) | ​ |  | 1.14 | ​ |  | 0.16 | ​ |  | (5.43) | ​ |  | (4.20) | ​
Total expenses | ​ |  | (0.04) | ​ |  | (0.06) | ​ |  | (0.13) | ​ |  | (0.22) | ​
Net increase (decrease) in net asset value | ​ |  | 1.10 | ​ |  | 0.10 | ​ |  | (5.56) | ​ |  | (4.42) | ​
Net asset value, end of period | ​ | $ | 11.35 | ​ | $ | 19.93 | ​ | $ | 11.35 | ​ | $ | 19.93 | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Total Return | ​ |  | 10.73 | % |  | 0.50 | % |  | (32.88) | % |  | (18.15) | %
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Ratios to Average Net Assets | ​ |  |  | ​ |  |  | ​ |  |  | ​ |  |  | ​
Total income (loss) | ​ |  | 14.92 | % |  | 5.62 | % |  | (36.50) | % |  | (7.66) | %
Management fees* | ​ |  | 0.60 | % |  | 0.60 | % |  | 0.60 | % |  | 0.60 | %
Expenses excluding management fees* | ​ |  | 0.73 | % |  | 0.67 | % |  | 0.81 | % |  | 0.74 | %
Net income (loss) | ​ |  | 14.59 | % |  | 5.30 | % |  | (37.56) | % |  | (8.66) | %
* | Annualized.

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