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Currency Gains / (Losses) (Tables) | 6 Months Ended
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Jun. 30, 2018
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Summary of Currency Gains and Losses Included in Income from Operations | Currency gains and losses, which are included in Income from operations, are as follows:
(in millions of Euros) |  | Notes |  |  | Three months ended June 30, 2018 |  |  | Three months ended June 30, 2017 |  |  | Six months ended June 30, 2018 |  |  | Six months ended June 30, 2017 |
Included in Revenue |  |  | 19 |  |  |  | 1 |  |  |  | 1 |  |  |  | 3 |  |  |  | (1 | )
Included in Cost of sales |  |  |  |  |  |  | 2 |  |  |  | (2 | ) |  |  | — |  |  |  | (2 | )
Included in Other gains / (losses) – net |  |  |  |  |  |  | 3 |  |  |  | 4 |  |  |  | 3 |  |  |  | (2 | )
Total |  |  |  |  |  |  | 6 |  |  |  | 3 |  |  |  | 6 |  |  |  | (5 | )
Realized exchange (losses) / gains on foreign currency derivatives – net |  |  | 19 |  |  |  | (1 | ) |  |  | (1 | ) |  |  | 1 |  |  |  | (11 | )
Unrealized gains on foreign currency derivatives – net |  |  | 19 |  |  |  | 4 |  |  |  | 7 |  |  |  | 3 |  |  |  | 13 |
Exchanges gains / (losses) from the remeasurement of monetary assets and liabilities – net |  |  |  |  |  |  | 3 |  |  |  | (3 | ) |  |  | 2 |  |  |  | (7 | )
Total |  |  |  |  |  |  | 6 |  |  |  | 3 |  |  |  | 6 |  |  |  | (5 | )

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