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FINANCIAL INSTRUMENTS - Sensitivity analysis (Details) - BRL (R$) R$ in Thousands | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019
Foreign currency risk |  |
Sensitivity analysis |  |
Percentage of change | 5.00% | 5.00%
Impact on income statement based on change in assumption | R$ 15,057 | R$ 112,355
Impact on income statement based on change in assumption, after effects of changes in net investment hedge | R$ 15,047 |
Foreign currency risk | Non-Deliverable Forwards |  |
Sensitivity analysis |  |
Percentage of change | 5.00% |
Impact on income statement based on change in assumption | R$ 3,703 |
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$ 85,147 | R$ 70,891
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
Products sold price risk |  |
Sensitivity analysis |  |
Percentage of change | 1.00% | 1.00%
Impact on income statement based on change in assumption | R$ 438,147 | R$ 396,440
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$ 269,454 | R$ 258,906

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