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FINANCE COSTS—NET (Details) - EUR (€) € in Millions | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Analysis of income and expense [line items] |  |  |
Interest received | € 0 | € 0 | € 7
Finance income | 0 | 0 | 7
Interest expense on borrowings | (117) | (124) | (118)
Interest expense on leases | (10) | (13) |
Interest expense on finance leases |  |  | (5)
Interest cost on pension and other benefits | (11) | (16) | (15)
Expenses on factoring arrangements | (10) | (19) | (18)
Realized and unrealized (losses) / gains on debt derivatives at fair value | (32) | 13 | 28
Realized and unrealized exchange (losses) / gains on financing activities - net | 37 | (3) | (22)
Other finance expenses | (17) | (16) | (10)
Capitalized borrowing costs | 1 | 3 | 4
Finance expenses | (159) | (175) | (156)
Finance costs - net | € (159) | € (175) | € (149)
Capitalization rate | 6.00% | 6.00% | 6.00%
Constellium SE Senior Notes |  |  |
Analysis of income and expense [line items] |  |  |
Interest expense on debt instruments issued | € 111 | € 115 |
Muscle Shoals' Senior Notes |  |  |
Analysis of income and expense [line items] |  |  |
Interest expense on debt instruments issued | € 3 |  |
Pan US ABL Facility |  |  |
Analysis of income and expense [line items] |  |  |
Interest expense on debt instruments issued |  | € 7 |
Constellium UACJ loan modification |  |  |
Analysis of income and expense [line items] |  |  |
Other finance expenses |  |  | € (6)

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