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v3.24.3

Per Share Information (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions | 3 Months Ended | 9 Months Ended |  |
--- | --- | --- | --- | ---
Sep. 29, 2024 | Oct. 01, 2023 | Sep. 29, 2024 | Oct. 01, 2023 | Sep. 03, 2024 | Dec. 31, 2023
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] |  |  |  |  |  |
Net income attributable to ATI | $ 82.7 | $ 90.2 | $ 230.7 | $ 265.1 |  |
Net income attributable to ATI after assumed conversions | $ 84.4 | $ 92.9 | $ 236.7 | $ 273.0 |  |
Denominator for basic net income per common share – weighted average shares | 128.7 | 128.1 | 126.5 | 128.4 |  |
Share-based compensation | 3.7 | 3.3 | 3.1 | 2.9 |  |
Denominator for diluted net income per common share – adjusted weighted average shares and assumed conversions | 146.8 | 150.2 | 146.9 | 150.1 |  |
Basic net income attributable to ATI per common share (in dollars per share) | $ 0.64 | $ 0.70 | $ 1.82 | $ 2.06 |  |
Diluted net income attributable to ATI per common share (in dollars per share) | $ 0.57 | $ 0.62 | $ 1.61 | $ 1.82 |  |
Antidilutive Securities Excluded from Computation of Earnings Per Share Amount | 0.0 | 0.0 | 0.0 | 0.0 |  |
Purchase of treasury stock | $ (40.0) | $ (45.0) | $ (190.0) | $ (55.1) |  |
Stock repurchase plan, authorized amount |  |  |  |  | $ 700.0 |
Treasury Stock, Shares, Acquired | 0.7 | 1.0 | 4.1 | 1.2 |  |
Share Repurchase Program, Utilized, Amount | $ 40.0 |  | $ 40.0 |  |  |
Purchase of treasury stock | (38.8) | $ (45.4) | (190.0) | $ (55.5) |  |
Treasury Stock |  |  |  |  |  |
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] |  |  |  |  |  |
Purchase of treasury stock | (38.8) | (45.4) | (190.0) | (55.5) |  |
ATI Inc. 3.5% Convertible Senior Notes due 2025 |  |  |  |  |  |
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] |  |  |  |  |  |
Convertible Senior Notes- Effect on numerator | $ 1.7 | $ 2.7 | $ 6.0 | $ 7.9 |  |
Convertible Senior Notes- Effect on denominator | 14.4 | 18.8 | 17.3 | 18.8 |  |
ATI Inc. 3.5% Convertible Senior Notes due 2025 | Convertible Debt |  |  |  |  |  |
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] |  |  |  |  |  |
Interest rate |  |  |  |  |  | 3.50%

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