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FINANCIAL INSTRUMENTS - Sensitivity analysis (Details) - BRL (R$) R$ in Thousands | 12 Months Ended
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Dec. 31, 2018 | Dec. 31, 2017
Interest Rate risk and Foreign Currency risk | Interest rate swaps and foreign currency swaps | Loans and Financing |  |
Sensitivity analysis |  |
Impact on income statement based on change in assumption | R$ 11,073 | R$ 6,479
Foreign currency risk |  |
Sensitivity analysis |  |
Percentage of change | 5.00% | 5.00%
Impact on income statement based on change in assumption | R$ 113,445 | R$ 129,209
Impact on income statement based on change in assumption, after effects of changes in net investment hedge | R$ 74,457 | R$ 79,088
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 | R$ 1,480
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$ 55,959 | R$ 54,908
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$ 476 |
Interest rate risk | Interest Rate Swap | Loans and Financing |  |
Sensitivity analysis |  |
Interest rate change (as a percent) | 0.10% | 0.10%
Products sold price risk |  |
Sensitivity analysis |  |
Percentage of change | 1.00% | 1.00%
Impact on income statement based on change in assumption | R$ 461,595 | R$ 369,176
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$ 296,234 | R$ 234,239

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