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10. BASIS OF CONSOLIDATION AND INVESTMENTS IN SUBSIDIARIES AND AFFILIATES (Details 3) - BRL (R$) R$ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
BasisOfConsolidationAndInvestmentsInSubsidiariesAndAffiliatesLineItems [Line Items] |  |  |  |  |  |
Equity in results of affiliated companies |  | R$ 124,324 | [1] | R$ 175,524 | [1] | R$ 135,706
Eliminations |  |  |  |  |  |
To cost of sales |  | (46,751) |  | (57,908) |  |
To taxes |  | 15,895 |  | 19,689 |  |
Others |  |  |  |  |  |
Amortizated at fair value - Investment in MRS |  | (11,747) |  | (11,747) |  |
Others |  | (9,966) |  | 157 |  |
Equity in results |  | 71,755 |  | 125,715 |  |
MRS Logistica S.A. [member] |  |  |  |  |  |
BasisOfConsolidationAndInvestmentsInSubsidiariesAndAffiliatesLineItems [Line Items] |  |  |  |  |  |
Equity in results of affiliated companies |  | 160,370 |  | 187,597 |  |
CSBI - Companhia Brasileira de Servicos de Infraestrutura [member] |  |  |  |  |  |
BasisOfConsolidationAndInvestmentsInSubsidiariesAndAffiliatesLineItems [Line Items] |  |  |  |  |  |
Equity in results of affiliated companies | [2] |  |  | 6,695 |  |
Transnordestina logistica s.a [member] |  |  |  |  |  |
BasisOfConsolidationAndInvestmentsInSubsidiariesAndAffiliatesLineItems [Line Items] |  |  |  |  |  |
Equity in results of affiliated companies |  | (28,952) |  | (17,100) |  |
Arvedi Metalfer do Brasil S.A. [member] |  |  |  |  |  |
BasisOfConsolidationAndInvestmentsInSubsidiariesAndAffiliatesLineItems [Line Items] |  |  |  |  |  |
Equity in results of affiliated companies |  | (6,765) |  | (1,682) |  |
Equimac S.A [member] |  |  |  |  |  |
BasisOfConsolidationAndInvestmentsInSubsidiariesAndAffiliatesLineItems [Line Items] |  |  |  |  |  |
Equity in results of affiliated companies |  | R$ (329) |  |  |  |
Other [member] |  |  |  |  |  |
BasisOfConsolidationAndInvestmentsInSubsidiariesAndAffiliatesLineItems [Line Items] |  |  |  |  |  |
Equity in results of affiliated companies |  |  |  | R$ 14 |  |
[1] | The table below shows the reconciliation of the equity in results of affiliated companies classified as joint venture and associates and the amount disclosed in the income statement and it is due to the elimination of the results of the CSN's transactions with these companies.
[2] | Refers to equity income until November 30, 2019, as of this date, the joint venture started to be controlled and consolidated, according to note 10 c.

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