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28. OPERATING COSTS AND EXPENSES (Details) - BRL (R$) R$ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Disclosure Of Operating Costs And Expenses [line items] |  |  |  |  |
Personnel |  | R$ 1,276 |  | R$ 1,410 |
Employees' and managers' profit sharing |  | 142 |  | 77 |
Post-employment benefits (reversals) - Note 24 |  | 438 |  | 337 |
Materials |  | 79 | R$ 91 | 104 |
Outsourced services |  | 1,265 | 1,239 | 1,087 |
Energy bought for resale |  | 12,111 |  | 11,084 |
Depreciation and amortization | [1] | 989 |  | 835 |
Operating provisions and adjustments for operating losses |  | 423 |  | 466 | [2]
Charges for use of the national grid |  | 1,748 |  | 1,480 |
Gas bought for resale |  | 1,083 |  | 1,238 |
Construction costs |  | 1,581 | 1,200 | 897 |
Other operating expenses, net |  | 297 |  | 405 |
Operating costs and expenses |  | R$ 21,432 | 22,475 | 19,420 |
Restated [member] |  |  |  |  |
Disclosure Of Operating Costs And Expenses [line items] |  |  |  |  |
Personnel |  |  | 1,272 |  |
Employees' and managers' profit sharing |  |  | 263 |  |
Post-employment benefits (reversals) - Note 24 |  |  | 408 |  |
Materials |  |  | 91 |  |
Outsourced services |  |  | 1,239 |  |
Energy bought for resale |  |  | 11,286 |  |
Depreciation and amortization | [1] |  | 958 |  |
Operating provisions and adjustments for operating losses | [3] |  | 2,401 | R$ 466 |
Charges for use of the national grid |  |  | 1,426 |  |
Gas bought for resale |  |  | 1,436 |  |
Construction costs |  |  | 1,200 |  |
Other operating expenses, net |  |  | 494 |  |
Operating costs and expenses |  |  | R$ 22,474 |  |
[1] | Net of PIS/Pasep and Cofins taxes applicable to amortization of the right-of-use assets in the amount of R$2.
[2] | See note 2.8.
[3] | For further details of restatement of comparative balances, see Note 2.8

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