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CURRENCY GAINS / (LOSSES) (Tables) | 12 Months Ended
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Dec. 31, 2020
Analysis of income and expense [abstract] |
Schedule of Currency Gains and Losses Included in Income from Operations |
|  |  |  | Year ended December 31,
(in millions of Euros) |  | Notes |  | 2020 |  | 2019 |  | 2018
Included in Revenue |  | 22 |  | (6) |  |  | (7) |  |  | 2 |
Included in Cost of sales |  |  |  | (2) |  |  | 1 |  |  | 2 |
Included in Other gains and losses - net |  |  |  | (19) |  |  | 9 |  |  | 7 |
Total |  |  |  | (27) |  |  | 3 |  |  | 11 |
Realized exchange (losses) / gains on foreign currency derivatives - net |  | 22 |  | (11) |  |  | 1 |  |  | 11 |
Losses reclassified from OCI as a result of hedge accounting discontinuation |  | 22 |  | (6) |  |  | — |  |  | — |
Unrealized (losses) / gains on foreign currency derivatives - net |  | 22 |  | (8) |  |  | 1 |  |  | (3) |
Exchange (losses) / gains from the remeasurement of monetary assets and liabilities - net |  |  |  | (2) |  |  | 1 |  |  | 3 |
Total |  |  |  | (27) |  |  | 3 |  |  | 11 |
Schedule of Foreign Currency Translation Reserve |
|  | At December 31,
(in millions of Euros) |  | 2020 |  | 2019
Foreign currency translation reserve at January 1 |  | 4 |  |  | 3 |
Effect of currency translation differences |  | (17) |  |  | 1 |
Foreign currency translation reserve at December 31 |  | (13) |  |  | 4 |

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