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v3.21.1

Supplementary cash flow information (Tables) | 12 Months Ended
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Dec. 31, 2020
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Partial Cash Paid for Investing Activities | Property, plant and equipment
|  | Year ended December 31, |
|  | 2018 |  |  | 2019 |  |  | 2020 |
|  | NT$000 |  |  | NT$000 |  |  | NT$000 |
Purchase of property, plant and equipment |  |  | 4,945,570 |  |  |  | 4,896,656 |  |  |  | 4,133,615 |
Add: Beginning balance of payable to contractors and equipment suppliers |  |  | 713,313 |  |  |  | 1,516,735 |  |  |  | 972,770 |
Add: Beginning balance of payable on lease |  |  | 29,842 |  |  |  | — |  |  |  | — |
Less: Ending balance of payable to contractors and equipment suppliers |  |  | (1,516,735 | ) |  |  | (972,770 | ) |  |  | (1,145,359 | )
Less: Ending balance of payable on lease |  |  | (17,792 | ) |  |  | — |  |  |  | — |
Cash paid during the year |  |  | 4,154,198 |  |  |  | 5,440,621 |  |  |  | 3,961,026 |

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