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FINANCIAL HIGHLIGHTS (Details) - $ / shares | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Per Share Operating Performance: |  |  |
Net asset value, beginning of year | $ 10.26 | $ 9.26 | $ 11.75
Total income (loss) | (1.74) | 1.09 | (2.40)
Net expenses | (0.09) | (0.09) | (0.09)
Net increase (decrease) in net asset value | (1.83) | 1.00 | (2.49)
Net asset value, end of year | $ 8.43 | $ 10.26 | $ 9.26
Total Return | (17.84%) | 10.80% | (21.19%)
Ratios to Average Net Assets |  |  |
Total income (loss) | (17.87%) | 9.73% | (29.05%)
Management fees | 0.75% | 0.75% | 0.75%
Total expenses excluding management fees | 1.86% | 1.08% | 0.74%
Expenses waived | (1.71%) | (0.93%) | (0.59%)
Net expenses excluding management fees | 0.15% | 0.15% | 0.15%
Net income (loss) | (18.77%) | 8.83% | (29.95%)

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