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Unaudited Interim Consolidated Statement of Changes in Equity - EUR (€) € in Millions | Total | Share capital [member] | Share premium [member] | Re-measurement [member] | Cash flow hedges [member] | Foreign currency translation reserve [member] | Other reserves [member] | Retained losses [member] | Total Equity holders of Constellium [member] | Non-controlling interests [member]
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Beginning balance at Dec. 31, 2016 | € (570) | € 2 | € 162 | € (151) | € (18) | € 12 | € 17 | € (603) | € (579) | € 9
Net income / (loss) | 28 |  |  |  |  |  |  | 29 | 29 | (1)
Other comprehensive income / (loss) | 22 |  |  | 15 | 20 | (13) |  |  | 22 |
Total comprehensive income / (loss) | 50 |  |  | 15 | 20 | (13) |  | 29 | 51 | (1)
Share-based compensation | 3 |  |  |  |  |  | 3 |  | 3 |
Transactions with non-controlling interests | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0
Ending balance at Jun. 30, 2017 | (517) | 2 | 162 | (136) | 2 | (1) | 20 | (574) | (525) | 8
Beginning balance at Dec. 31, 2016 | (570) | 2 | 162 | (151) | (18) | 12 | 17 | (603) | (579) | 9
Net income / (loss) | (31) |  |  |  |  |  |  | (31) | (31) |
Other comprehensive income / (loss) | 15 |  |  | 4 | 31 | (19) |  |  | 16 | (1)
Total comprehensive income / (loss) | (16) |  |  | 4 | 31 | (19) |  | (31) | (15) | (1)
Share issuance | 259 | 1 | 258 |  |  |  |  |  | 259 |
Share-based compensation | 8 |  |  |  |  |  | 8 |  | 8 |
Transactions with non-controlling interests | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0
Ending balance (Restated [member]) at Dec. 31, 2017 | (321) | 3 | 420 | (147) | 13 | (7) | 25 | (636) | (329) | 8
Ending balance at Dec. 31, 2017 | (319) | 3 | 420 | (147) | 13 | (7) | 25 | (634) | (327) | 8
Change in accounting policies ending balance at Dec. 31,2017 | Change in accounting policies [member] | (2) |  |  |  |  |  |  | (2) | (2) |
Net income / (loss) | 31 |  |  |  |  |  |  | 31 | 31 |
Other comprehensive income / (loss) | 12 |  |  | 20 | (9) | 1 |  |  | 12 |
Total comprehensive income / (loss) | 43 |  |  | 20 | (9) | 1 |  | 31 | 43 |
Share-based compensation | 6 |  |  |  |  |  | 6 |  | 6 |
Transactions with non-controlling interests | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0
Ending balance at Jun. 30, 2018 | € (272) | € 3 | € 420 | € (127) | € 4 | € (6) | € 31 | € (605) | € (280) | € 8

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