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v3.20.1

SUBSEQUENT EVENTS (Details) |  | 1 Months Ended | 3 Months Ended | 6 Months Ended | 132 Months Ended | 142 Months Ended
--- | --- | --- | --- | --- | --- | ---
Aug. 31, 2007 shares | May 08, 2020 USD ($) $ / item shares | Sep. 30, 2007 shares | Mar. 31, 2020 USD ($) shares | Mar. 31, 2019 USD ($) shares | Dec. 31, 2007 shares | Jun. 30, 2019 shares | Dec. 31, 2018 shares | Jun. 30, 2019 USD ($) $ / item
Subsequent events |  |  |  |  |  |  |  |  |
Number of depository receipts repurchased | shares | 14,283 |  | 14,283 |  |  | 14,283 | 14,283 | 14,283 |
Repurchase price of depository receipts (in dollars per receipt) | $ / item |  |  |  |  |  |  |  |  | 28.42
Total cost of repurchase |  |  |  | $ 389,947 | $ 2,930,736 |  |  |  | $ 44,714,000
Units required to be repurchased (in shares) | shares |  |  |  | 219 | 1,795 |  |  |  |
Subsequent event |  |  |  |  |  |  |  |  |
Subsequent events |  |  |  |  |  |  |  |  |
Number of depository receipts repurchased | shares |  | 76 |  |  |  |  |  |  |
Repurchase price of depository receipts (in dollars per receipt) | $ / item |  | 42.95 |  |  |  |  |  |  |
Price per unit of depository receipts | $ / item |  | 1,288.50 |  |  |  |  |  |  |
Total cost of repurchase |  | $ 3,265 |  |  |  |  |  |  |
Class B |  |  |  |  |  |  |  |  |
Subsequent events |  |  |  |  |  |  |  |  |
Number of depository receipts repurchased | shares | 3,571 |  | 3,571 |  | 3,571 |  |  | 3,571 |
Total cost of repurchase |  |  |  | $ 3,900 | $ 556,828 |  |  |  |
Class B | Subsequent event |  |  |  |  |  |  |  |  |
Subsequent events |  |  |  |  |  |  |  |  |
Units required to be repurchased (in shares) | shares |  | 0.6 |  |  |  |  |  |  |
Value of units required to be repurchased |  | $ 775 |  |  |  |  |  |  |
General Partnership |  |  |  |  |  |  |  |  |
Subsequent events |  |  |  |  |  |  |  |  |
Number of depository receipts repurchased | shares | 188 |  | 188 |  | 188 |  |  | 188 |
Total cost of repurchase |  |  |  | 311,952 | $ 29,307 |  |  |  |
Value of units required to be repurchased |  |  |  | $ 3,898 |  |  |  |  |
General Partnership | Subsequent event |  |  |  |  |  |  |  |  |
Subsequent events |  |  |  |  |  |  |  |  |
Value of units required to be repurchased |  | $ 41 |  |  |  |  |  |  |

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