To estimate **FFO / Net debt** for 2022:

1. **Funds from operations (FFO)** is commonly approximated as:
   \[
   \text{FFO} = \text{Cash flow from operating activities} - \text{working capital effects}
   \]
   Using the provided cash-flow data:
   - Cash flows from operating activities, 2022 = **€458.926m**
   - Increase/decrease in working capital and other operating activities, 2022 = **€113.840m**

   Since operating cash flow after working capital is lower by this working-capital absorption, estimated FFO before working capital is:
   \[
   458.926 + 113.840 = 572.766 \text{ million}
   \]

2. **Net debt** can be approximated from financial liabilities less cash and financial assets. Using year-end 2022 balance sheet items:
   - Other noncurrent financial liabilities = **€1,751.255m**
   - Noncurrent lease liabilities = **€150.955m**
   - Other current financial liabilities = **€389.716m**
   - Current lease liabilities = **€6.362m**
   - Current financial liabilities at fair value through profit or loss = **€76.644m**
   - Noncurrent financial liabilities at fair value through profit or loss = **€0.000m**

   Gross financial debt:
   \[
   1,751.255 + 150.955 + 389.716 + 6.362 + 76.644 = 2,374.932 \text{ million}
   \]

   Deduct:
   - Cash and cash equivalents = **€392.811m**
   - Other current financial assets = **€211.136m**
   - Current financial assets at fair value through profit or loss = **€141.568m**
   - Other noncurrent financial assets = **€38.792m**
   - Noncurrent financial assets at fair value through profit or loss = **€33.225m**

   Total financial assets and cash:
   \[
   392.811 + 211.136 + 141.568 + 38.792 + 33.225 = 817.532 \text{ million}
   \]

   Estimated net debt:
   \[
   2,374.932 - 817.532 = 1,557.400 \text{ million}
   \]

3. Therefore:
   \[
   \text{FFO / Net debt} = \frac{572.766}{1,557.400} = 0.3678
   \]

<answer>0.368</answer>