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Capital stock (Tables) | 12 Months Ended
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Dec. 31, 2020
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Movement of Ordinary Shares Issued | Movements in the number of the Company’s ordinary shares outstanding are as follows:
|  | 2018 |  |  | 2019 |  |  | 2020 |
|  | in thousands |  |  | in thousands |  |  | in thousands |
January 1 |  |  | 856,059 |  |  |  | 727,265 |  |  |  | 727,240 |
Restricted shares – cancelled |  |  | (349 | ) |  |  | (25 | ) |  |  | — |
Restricted shares – uncancelled |  |  | (23 | ) |  |  | — |  |  |  | — |
Capital reduction |  |  | (128,422 | ) |  |  | — |  |  |  | — |
December 31 |  |  | 727,265 |  |  |  | 727,240 |  |  |  | 727,240 |
Movement of Treasury Stock | On March 7, 2019 and August 6, 2019, the Company’s Board of Directors approved the cancellation of treasury stock 25,570 thousand shares amounted to NT$962,503 thousand. As of December 31, 2019, all of the Company’s treasury stocks were cancelled. As of December 31, 2018, the reasons for share repurchases and movements in the number of the Company’s treasury stock is as follows:
|  | 2018 |
|  | Shares |  |  | Amount |
|  | in thousands |  |  | NT$000 |
January 1 |  |  | 30,085 |  |  |  | 1,007,654 |
Capital reduction |  |  | (4,515 | ) |  |  | (45,151 | )
December 31 |  |  | 25,570 |  |  |  | 962,503 |

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