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GOODWILL - Goodwill by segment (Details) - BRL (R$) R$ in Thousands | Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
--- | --- | --- | --- | ---
Goodwill by segment |  |  |  |
Goodwill | R$ 12,427,527 | R$ 12,103,519 | R$ 9,469,311 | R$ 9,112,390
Brazil |  |  |  |
Goodwill by segment |  |  |  |
Goodwill | 373,135 | 373,135 | 373,135 |
Special Steel |  |  |  |
Goodwill by segment |  |  |  |
Goodwill | 4,111,619 | 3,828,841 | 2,969,752 |
North America |  |  |  |
Goodwill by segment |  |  |  |
Goodwill | R$ 7,942,773 | R$ 7,901,543 | R$ 6,126,424 |

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