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v3.25.3

Goodwill - Key assumptions for cash-generating units (Details) | Sep. 30, 2025 | Sep. 30, 2024
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Maximum |  |
Disclosure of information for cash-generating units [line items] |  |
Long-term growth rate of net operating cash flows |  | 2.00%
Western and Southern Europe |  |
Disclosure of information for cash-generating units [line items] |  |
Pre-tax WACC | 9.70% | 10.30%
Long-term growth rate of net operating cash flows | 2.00% | 2.00%
U.S. Commercial and State Government |  |
Disclosure of information for cash-generating units [line items] |  |
Pre-tax WACC | 11.30% | 11.40%
Long-term growth rate of net operating cash flows | 2.00% | 2.00%
U.S. Federal |  |
Disclosure of information for cash-generating units [line items] |  |
Pre-tax WACC | 11.40% | 10.30%
Long-term growth rate of net operating cash flows | 2.00% | 2.00%
Canada |  |
Disclosure of information for cash-generating units [line items] |  |
Pre-tax WACC | 9.10% | 10.90%
Long-term growth rate of net operating cash flows | 2.00% | 2.00%
Scandinavia, Northwest and Central- East Europe |  |
Disclosure of information for cash-generating units [line items] |  |
Pre-tax WACC | 8.50% |
Long-term growth rate of net operating cash flows | 2.00% |
Scandinavia and Central Europe |  |
Disclosure of information for cash-generating units [line items] |  |
Pre-tax WACC |  | 10.00%
Long-term growth rate of net operating cash flows |  | 2.00%
U.K. and Australia |  |
Disclosure of information for cash-generating units [line items] |  |
Pre-tax WACC | 11.10% | 11.50%
Long-term growth rate of net operating cash flows | 2.00% | 2.00%
Germany |  |
Disclosure of information for cash-generating units [line items] |  |
Pre-tax WACC | 10.10% |
Long-term growth rate of net operating cash flows | 1.90% |
Northwest And Central-East Europe |  |
Disclosure of information for cash-generating units [line items] |  |
Pre-tax WACC |  | 10.20%
Long-term growth rate of net operating cash flows |  | 2.00%
Finland, Poland and Baltics |  |
Disclosure of information for cash-generating units [line items] |  |
Pre-tax WACC | 9.90% | 10.30%
Long-term growth rate of net operating cash flows | 2.00% | 2.00%
Asia Pacific |  |
Disclosure of information for cash-generating units [line items] |  |
Pre-tax WACC | 15.90% | 17.80%
Long-term growth rate of net operating cash flows | 2.00% | 2.00%

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