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FINANCIAL INSTRUMENTS - Sensitivity analysis (Details) - BRL (R$) R$ in Thousands |  | 12 Months Ended
--- | --- | ---
Dec. 31, 2019 | Dec. 31, 2019 | Dec. 31, 2018
Interest Rate risk and Foreign Currency risk | Interest rate swaps and foreign currency swaps | Loans and Financing |  |  |
Sensitivity analysis |  |  |
Interest rate change (as a percent) |  | 0.10% | 0.10%
Impact on income statement based on change in assumption |  |  | R$ 11,073
Foreign currency risk |  |  |
Sensitivity analysis |  |  |
Percentage of change |  | 5.00% | 5.00%
Impact on income statement based on change in assumption |  | R$ 112,355 | R$ 113,445
Impact on income statement based on change in assumption, after effects of changes in net investment hedge |  | R$ 71,718 | R$ 74,457
Foreign currency risk | Non-Deliverable Forwards |  |  |
Sensitivity analysis |  |  |
Percentage of change |  | 5.00% | 5.00%
Impact on income statement based on change in assumption |  |  | R$ 7,063
Interest rate risk |  |  |
Sensitivity analysis |  |  |
Interest rate change (as a percent) |  | 0.10% | 0.10%
Impact on income statement based on change in assumption |  | R$ 70,891 | R$ 55,959
Interest rate risk | Interest Rate Swap |  |  |
Sensitivity analysis |  |  |
Interest rate change (as a percent) |  | 0.50% | 0.50%
Impact on income statement based on change in assumption | R$ 408 |  | R$ 476
Products sold price risk |  |  |
Sensitivity analysis |  |  |
Percentage of change |  | 1.00% | 1.00%
Impact on income statement based on change in assumption |  | R$ 396,440 | R$ 461,595
Raw materials and commodity price risk |  |  |
Sensitivity analysis |  |  |
Percentage of change |  | 1.00% | 1.00%
Impact on income statement based on change in assumption |  | R$ 258,906 | R$ 296,234

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