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27. EMPLOYEE BENEFITS (Details 16) | 12 Months Ended
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Dec. 31, 2018 | Dec. 31, 2017
Disclosure of defined benefit plans [line items] |  |
General mortality table | 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. | 35% and Average Salary Supplementation Plans : AT 2000 segregated by gender (10% smoothed)
Disability mortality table | Winklevoss - 1% | Winklevoss - 1%
Inflation | 4.75% | 5.00%
Post-employment healthcare benefits |  |
Disclosure of defined benefit plans [line items] |  |
General mortality table | AT 2000 segregated by gender | AT 2000 segregated by gender
Disability mortality table | Winklevoss with death probabilities reduced by 1% in all ages | Winklevoss with death probabilities reduced by 1% in all ages
Actuarial nominal discount rate | 9.62% | 10.34%
Inflation | 4.75% | 5.00%
Real increase in medical costs based on age (Aging Factor) | 0.5% - 3.00%real a.a | 0.5% - 3.00%real a.a
Nominal increase medical costs growth rate | 8.15% | 8.41%
Average medical cost | 1054.65 | 1,001.69

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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 2018-01-01 -Paragraph 144 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=19&date=2018-03-01&anchor=para_144&doctype=Standard -URIDate 2018-03-16 + Details
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- Definition Medical cost trend rate used as significant actuarial assumption to determine the present value of a defined benefit obligation. [Refer: Defined benefit obligation, at present value; Actuarial assumptions [member]] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 19 -IssueDate 2018-01-01 -Paragraph 144 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=19&date=2018-03-01&anchor=para_144&doctype=Standard -URIDate 2018-03-16 + Details
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