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30. EMPLOYEE BENEFITS (Details 7) | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019
Disclosure of defined benefit plans [abstract] |  |
Actuarial financing method | Projected unit credit | Projected unit credit
Functional currency | Real (R$) | Real (R$)
Recognition of plan assets | Fair value | Fair value
Nominal discount rate | Millennium Plan: 6,95% Plan 35%: 6,24% Supplementation : 6,44% | Millennium Plan: 6,98% Plan 35%: 6,75% Supplementation: 6,81%
Inflation rate | 3.32% | 3.61%
Nominal salary increase rate | 4.35% | 4.65%
Nominal benefit increase rate | 3.32% | 3.61%
Rate of return on investments | Millennium Plan: 6,95% Plan 35%: 6,24% Supplementation : 6,44% | Millennium Plan: 6,98% Plan 35%: 6,75% Supplementation: 6,81%
General mortality table | Millennium Plan: AT-2012 segregated by gender Plan 35%: AT-2000 Male aggravated by 15% Supplementation: AT-2000 aggravated by 10% segregated by gender | Millennium Plan: AT-2000 smoothed down by 10% segregated by gender Plan 35%: AT-2000 Male aggravated by 15% Supplementation: AT-2000 aggravated by 10% segregated by gender
Disability table | 35% Plan Light Medium. Millenium Plan: Prudential (-10%) Supplementation: not applicable | 35% Plan and Supplementation: Light Medium. Millenium Plan: Prudential (Ferr. Retirement)
Disability mortality table | Millenium Plan: AT-71 35% Plan : MI-2006 -10% M&F Supplementation: Winklevoss -10% | Winklevoss - 1%
Turnover table | Millenium plan 5% per annum, zero for plans 35% and Supplementation | Millenium plan 5% per annum, zero for plans 35% and Supplementation
Retirement age | 100% on the first date he/she becomes eligible for programmed retirement benefit under the plan | 100% on the first date he/she becomes eligible for programmed retirement benefit under the plan
Household of active participants | 95% will be married at the time of retirement, with the wife being 4 years younger than the husband | 95% will be married at the time of retirement, with the wife being 4 years younger than the husband

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- Definition The expected rate of inflation that is used as a significant actuarial assumption to determine the present value of a defined benefit obligation. [Refer: Defined benefit plans [member]; Defined benefit obligation, at present value; Actuarial assumptions [member]] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 19 -IssueDate 2020-01-01 -Paragraph 144 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=19&code=ifrs-tx-2020-en-r&anchor=para_144&doctype=Standard -URIDate 2020-01-01 + Details
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- Definition The expected rate of increases in pension that is used as a significant actuarial assumption to determine the present value of a defined benefit obligation. [Refer: Defined benefit plans [member]; Defined benefit obligation, at present value; Actuarial assumptions [member]] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 19 -IssueDate 2020-01-01 -Paragraph 144 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=19&code=ifrs-tx-2020-en-r&anchor=para_144&doctype=Standard -URIDate 2020-01-01 + Details
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- Definition The expected rate of salary increases used as a significant actuarial assumption to determine the present value of a defined benefit obligation. [Refer: Defined benefit plans [member]; Defined benefit obligation, at present value; Actuarial assumptions [member]] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 19 -IssueDate 2020-01-01 -Paragraph 144 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=19&code=ifrs-tx-2020-en-r&anchor=para_144&doctype=Standard -URIDate 2020-01-01 + Details
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- Definition The description of the currency of the primary economic environment in which the entity operates. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 21 -IssueDate 2020-01-01 -Paragraph 53 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=21&code=ifrs-tx-2020-en-r&anchor=para_53&doctype=Standard -URIDate 2020-01-01 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 21 -IssueDate 2020-01-01 -Paragraph 57 -Subparagraph c -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=21&code=ifrs-tx-2020-en-r&anchor=para_57_c&doctype=Standard -URIDate 2020-01-01 + Details
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