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Earnings Per Share (Tables) | 12 Months Ended
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Dec. 31, 2017
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Earning Per Share |
(in millions of Euros) |  | Year ended December 31, 2017 |  |  | Year ended December 31, 2016 |  |  | Year ended December 31, 2015 |
Earnings attributable to equity holders of the parent used to calculate basic and diluted earnings per share |  |  | (31 | ) |  |  | (4 | ) |  |  | (554 | )
Number of shares attributable to equity holders of Constellium
(number of shares) |  | Year ended December 31, 2017 |  |  | Year ended December 31, 2016 |  |  | Year ended December 31, 2015 |
Weighted average number of ordinary shares used to calculate basic earnings per share |  |  | 110,164,320 |  |  |  | 105, 500,327 |  |  |  | 105,097,442 |
Effect of other dilutive potential ordinary shares(A) |  |  | — |  |  |  | — |  |  |  | — |
Weighted average number of ordinary shares used to calculate diluted earnings per share |  |  | 110,164,320 |  |  |  | 105, 500,327 |  |  |  | 105,097,442 |
(A) | For the years ended December 31, 2017, 2016 and 2015, there were 3,291,875, 411,902 and 510,721 potential ordinary shares respectively that could have a dilutive impact but were considered antidilutive due to negative earnings.
Earnings per share attributable to the equity holders of Constellium
(in Euro per share) |  | Year ended December 31, 2017 |  |  | Year ended December 31, 2016 |  |  | Year ended December 31, 2015 |
Basic |  |  | (0.28 | ) |  |  | (0.04 | ) |  |  | (5.27 | )
Diluted |  |  | (0.28 | ) |  |  | (0.04 | ) |  |  | (5.27 | )

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- Definition The disclosure of earnings per share. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 33 -IssueDate 2017-01-01 -Paragraph 66 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=33&date=2017-03-01&anchor=para_66&doctype=Standard -URIDate 2017-03-09 + Details
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