S&P-style FFO is commonly approximated from cash flow from operations before working-capital movements, with interest adjusted on a gross basis:

- Cash flows from operating activities, 2022: €1,648m  
- Increase/decrease in working capital, 2022: +€135m  
- CFO before working capital: €1,648m − €135m = €1,513m  
- Interest paid: €209m  

Estimated FFO = CFO before working capital + interest paid  
= €1,513m + €209m  
= €1,722m

For net debt, use reported financial debt including bonds/other marketable debt, loans, and lease liabilities, less cash and cash equivalents:

Debt items at 2022 year-end / 2023-01-01:
- Noncurrent bonds/marketable debt: €3,101m  
- Noncurrent loans: €2,624m  
- Noncurrent lease liabilities: €439m  
- Current bonds/marketable debt: €1,139m  
- Current loans: €553m  
- Current lease liabilities: €72m  

Gross debt = €3,101m + €2,624m + €439m + €1,139m + €553m + €72m  
= €7,928m

Cash and cash equivalents = €2,360m

Net debt = €7,928m − €2,360m  
= €5,568m

FFO / Net debt = €1,722m / €5,568m = 0.3093, or about 30.9%.

<answer>30.9%</answer>