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27. EMPLOYEE BENEFITS (Details 8) | 12 Months Ended
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Dec. 31, 2018 | Dec. 31, 2017
Plan covering 35% of the average salary | Male |  |
Disclosure of defined benefit plans [line items] |  |
Average life expectancy of employees (in years) | 18 | 21
Average life expectancy in years of employees who are 40 (in years) | 40 | 43
Plan covering 35% of the average salary | Female |  |
Disclosure of defined benefit plans [line items] |  |
Average life expectancy of employees (in years) | 18 | 23
Average life expectancy in years of employees who are 40 (in years) | 40 | 47
Average salary supplementation plan | Male |  |
Disclosure of defined benefit plans [line items] |  |
Average life expectancy of employees (in years) | 18.74 | 20.45
Average life expectancy in years of employees who are 40 (in years) | 40.6 | 42.69
Average salary supplementation plan | Female |  |
Disclosure of defined benefit plans [line items] |  |
Average life expectancy of employees (in years) | 22.23 | 23.02
Average life expectancy in years of employees who are 40 (in years) | 45.37 | 46.29
Milenio Plan | Male |  |
Disclosure of defined benefit plans [line items] |  |
Average life expectancy of employees (in years) | 21 | 21
Average life expectancy in years of employees who are 40 (in years) | 43 | 43
Milenio Plan | Female |  |
Disclosure of defined benefit plans [line items] |  |
Average life expectancy of employees (in years) | 23 | 23
Average life expectancy in years of employees who are 40 (in years) | 47 | 47

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