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Other gains and losses (Tables) | 12 Months Ended
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Dec. 31, 2020
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Summary of Other gains and losses |
|  | Year ended December 31, |
|  | 2018 |  |  | 2019 |  |  | 2020 |
|  | NT$000 |  |  | NT$000 |  |  | NT$000 |
Foreign exchange gains (losses), net |  |  | 93,104 |  |  |  | (154,993 | ) |  |  | (355,255 | )
Reimbursement of ADSs service charge |  |  | 13,269 |  |  |  | 4,292 |  |  |  | 2,101 |
Gain on valuation of financial assets at fair value through profit or loss |  |  | 1,485 |  |  |  | 1,317 |  |  |  | 24,015 |
Others |  |  | 6,851 |  |  |  | 970 |  |  |  | 5,872 |
|  |  | 114,709 |  |  |  | (148,414 | ) |  |  | (323,267 | )

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