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UNALLOCATED RESERVE AND DISTRIBUTIONS (Details) - USD ($) | 3 Months Ended | 12 Months Ended
--- | --- | ---
Jan. 31, 2019 | Oct. 31, 2018 | Jul. 31, 2018 | Apr. 30, 2018 | Jan. 31, 2018 | Oct. 31, 2017 | Jul. 31, 2017 | Apr. 30, 2017 | Jan. 31, 2019 | Jan. 31, 2018 | Jan. 31, 2017
UNALLOCATED RESERVE AND DISTRIBUTIONS |  |  |  |  |  |  |  |  |  |  |
Distribution declared or paid (in dollars per unit) |  |  |  |  |  |  |  |  | $ 2.79 | $ 1.49 | $ 0.55
Unallocated Cash and Securities portion of Unallocated Reserve |  |  |  |  |  |  |  |  |  |  |
Cash and U.S. Government securities | $ 33,004,122 |  |  |  | $ 24,112,286 |  |  |  | $ 33,004,122 | $ 24,112,286 |
Distribution payable | (18,236,814) |  |  |  | (15,481,612) |  |  |  | (18,236,814) | (15,481,612) |
Unallocated cash and U.S. Government securities | 14,767,308 |  |  |  | 8,630,674 |  |  |  | 14,767,308 | 8,630,674 |
Reconciliation of Trust's Unallocated Reserve |  |  |  |  |  |  |  |  |  |  |
Unallocated Reserve at the beginning of the period |  |  |  | $ 10,606,675 |  |  |  |  | 10,606,675 |  |
Net income | 6,786,679 | $ 13,585,062 | $ 18,871,455 | $ 6,315,848 | 4,256,877 | $ 10,697,669 | $ 13,996,954 | $ 4,471,925 | 45,559,044 | 33,423,425 | $ 9,763,771
Distributions declared |  |  |  |  |  |  |  |  | (39,360,030) |  |
Unallocated Reserve at the end of the period | $ 16,805,689 |  |  |  | $ 10,606,675 |  |  |  | $ 16,805,689 | $ 10,606,675 |
Distribution declared per unit |  |  |  |  |  |  |  |  | $ 1.39 | $ 1.18 | $ 0.14

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