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OPERATING SEGMENT INFORMATION - Segment Adjusted EBITDA and reconciliation of Adjusted EBITDA to Net Income (Details) - EUR (€) € in Millions | 1 Months Ended | 12 Months Ended
--- | --- | ---
Jul. 31, 2018 | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Disclosure of segment adjusted EBITDA and reconciliation of adjusted EBITDA to net income [line items] |  |  |  |
Adjusted EBITDA |  | € 465 | € 562 | € 498
Metal price lag |  | (8) | (46) | 0
Start-up and development costs |  | (5) | (11) | (21)
Bowling Green one-time costs related to the acquisition |  | 0 | (5) | 0
Share based compensation costs |  | (15) | (16) | (12)
Gains on pension plan amendments |  | (2) | 1 | 36
Depreciation and amortization |  | (259) | (256) | (197)
Impairment of assets |  | (43) | 0 | 0
Restructuring costs |  | (13) | (4) | (1)
Unrealized gains / (losses) on derivatives |  | 16 | 33 | (84)
Unrealized exchange gains from the remeasurement of monetary assets and liabilities - net |  | 1 | 0 | 0
(Losses) / gains on disposals |  | (4) | (3) | 186
Other |  | (8) | 0 | (1)
Income from operations |  | 125 | 255 | 404
Finance costs - net |  | (159) | (175) | (149)
Share of income / (loss) of joint-ventures |  | 0 | 2 | (33)
(Loss) / income before income tax |  | (34) | 82 | 222
Income tax benefit / (expense) |  | 17 | (18) | (32)
Net (loss) / income |  | (17) | 64 | 190
Losses reclassified from OCI as a result of hedge accounting discontinuation |  | 6 | 0 | 0
COVID-19 |  |  |  |
Disclosure of segment adjusted EBITDA and reconciliation of adjusted EBITDA to net income [line items] |  |  |  |
Procurement penalties and termination fees |  | (2) |  |
Losses reclassified from OCI as a result of hedge accounting discontinuation |  | 6 |  |
Novelis |  |  |  |
Disclosure of segment adjusted EBITDA and reconciliation of adjusted EBITDA to net income [line items] |  |  |  |
Sale of assets | € 200 |  |  |
Net gain on sale of assets |  |  |  | 190
P&ARP |  |  |  |
Disclosure of segment adjusted EBITDA and reconciliation of adjusted EBITDA to net income [line items] |  |  |  |
Adjusted EBITDA |  | 291 | 273 | 243
A&T |  |  |  |
Disclosure of segment adjusted EBITDA and reconciliation of adjusted EBITDA to net income [line items] |  |  |  |
Adjusted EBITDA |  | 106 | 204 | 152
AS&I |  |  |  |
Disclosure of segment adjusted EBITDA and reconciliation of adjusted EBITDA to net income [line items] |  |  |  |
Adjusted EBITDA |  | 88 | 106 | 125
H&C |  |  |  |
Disclosure of segment adjusted EBITDA and reconciliation of adjusted EBITDA to net income [line items] |  |  |  |
Adjusted EBITDA |  | € (20) | € (21) | € (22)

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