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Earnings Per Share (Tables) | 6 Months Ended
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Jun. 30, 2018
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Earning Per Share |
(in millions of Euros) |  | Three months ended June 30, 2018 |  |  | Three months ended June 30, 2017 |  |  | Six months ended June 30, 2018 |  |  | Six months ended June 30, 2017 |
Earnings attributable to equity holders of the parent used to calculate basic and diluted earnings per share |  |  | 55 |  |  |  | 16 |  |  |  | 31 |  |  |  | 29 |
Number of shares attributable to equity holders of Constellium
(number of shares) |  | Three months ended June 30, 2018 |  |  | Three months ended June 30, 2017 |  |  | Six months ended June 30, 2018 |  |  | Six months ended June 30, 2017 |
Weighted average number of ordinary shares used to calculate basic earnings per share |  |  | 134,562,177 |  |  |  | 105,557,517 |  |  |  | 134,517,869 |  |  |  | 105,553,573 |
Effect of other dilutive potential ordinary shares(A) |  |  | 4,471,455 |  |  |  | 1,146,397 |  |  |  | 4,515,005 |  |  |  | 1,150,819 |
Weighted average number of ordinary shares used to calculate diluted earnings per share |  |  | 139,033,632 |  |  |  | 106,703,914 |  |  |  | 139,032,874 |  |  |  | 106,704,392 |
(A) | For the six months ended June 30, 2018 and 2017, potential dilutive new ordinary shares to be issued are part of share-based compensation plans.
Earnings per share attributable to the equity holders of Constellium
(in Euro per share) |  | Three months ended June 30, 2018 |  |  | Three months ended June 30, 2017 |  |  | Six months ended June 30, 2018 |  |  | Six months ended June 30, 2017 |
Basic |  |  | 0.41 |  |  |  | 0.15 |  |  |  | 0.23 |  |  |  | 0.27 |
Diluted |  |  | 0.39 |  |  |  | 0.15 |  |  |  | 0.22 |  |  |  | 0.27 |

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