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v3.21.1

SUBSEQUENT EVENTS (Details) - USD ($) |  |  | 1 Months Ended | 3 Months Ended | 6 Months Ended | 132 Months Ended |  |
--- | --- | --- | --- | --- | --- | --- | --- | ---
Jul. 31, 2014 | Aug. 31, 2007 | Sep. 30, 2007 | Dec. 31, 2007 | Jun. 30, 2019 | Dec. 31, 2018 | Oct. 31, 2020 | Aug. 31, 2017
Subsequent events |  |  |  |  |  |  |  |
Number of depository receipts repurchased |  | 1,428,437 | 1,428,437 | 1,428,437 | 1,428,437 | 1,428,437 |  |
Line of Credit |  |  |  |  |  |  |  |
Subsequent events |  |  |  |  |  |  |  |
Maximum borrowings | $ 25,000,000 |  |  |  |  |  |  |
Term of debt | 3 years |  |  |  |  |  |  |
Amount of refinancing costs |  |  |  |  |  |  | $ 37,500 | $ 128,000
Line of Credit | Federal Funds Rate |  |  |  |  |  |  |  |
Subsequent events |  |  |  |  |  |  |  |
Variable interest rate spread | 0.50% |  |  |  |  |  |  |
Line of Credit | LIBOR |  |  |  |  |  |  |  |
Subsequent events |  |  |  |  |  |  |  |
Additional applicable margin rate | 2.50% |  |  |  |  |  |  |
Variable interest rate spread | 1.00% |  |  |  |  |  |  |

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