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26 EMPLOYEE BENEFITS (Details 7) | 12 Months Ended
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Dec. 31, 2019 | Dec. 31, 2018
Employee Benefits [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: 6.98% Plan 35%: 6.75% Supplementation: 6.81% | Millennium Plan: 9.69% Plan 35%: 9.60% Supplementation: 9.59%
Inflation rate | 3.61% | 4.75%
Nominal salary increase rate | 4.65% | 5.80%
Nominal benefit increase rate | 3.61% | 4.75%
General mortality table | Millennium Plan: 9.69% Plan 35%: 9.60% Supplementation: 9.59% | Millennium Plan: AT-2000 smoothed down by 10% segregated by gender. Plans 35%: AT-2000 Male aggravated by 15%. Supplementation: AT-2000 aggravated by 10% segregated by gender.
Disability table | 35% Plan and Supplementation: Light Medium. Millenium Plan: Prudential (Ferr. Retirement) | 35% Plan and Supplementation: Light Medium. Millenium Plan: Prudential (Ferr. Retirement)
Disability mortality table | Winklevoss - 1% | 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 composition 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 2019-01-01 -Paragraph 144 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=19&code=ifrs-tx-2019-en-r&anchor=para_144&doctype=Standard -URIDate 2019-03-27 + 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 2019-01-01 -Paragraph 144 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=19&code=ifrs-tx-2019-en-r&anchor=para_144&doctype=Standard -URIDate 2019-03-27 + 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 2019-01-01 -Paragraph 144 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=19&code=ifrs-tx-2019-en-r&anchor=para_144&doctype=Standard -URIDate 2019-03-27 + Details
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