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v3.22.1

The margin defined for each performance obligation from the transmission concession contract is as follows: (Details) - BRL (R$) R$ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Construction and upgrades revenue | R$ 252 | R$ 201 | R$ 312 | [1]
Construction and upgrades costs | (183) | (147) | (220) | [1]
Margin | R$ 69 | R$ 54 | R$ 92 | [1]
Mark-up (%) | 37.40% | 36.73% | 41.82% |
Operation and maintenance revenue | R$ 355 | R$ 279 | R$ 352 | [1]
Operation and maintenance cost | (235) | (223) | (388) | [1]
Margin | R$ 120 | R$ 56 | R$ (36) | [1]
Mark-up (%) | 50.88% | 25.11% | 9.28% |
[1] | The negative margin observed in 2019 related to the performance obligation to operate and maintain is due the recognition of the non-recurring tax provision, in the amount of R$135.

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