To estimate the Net Debt / EBITDA ratio for 2022, we follow the S&P methodology:

1. **Total debt** – sum of interest‑bearing liabilities:
   - Long‑term borrowings (2023‑01‑01): €8,416,700,000  
   - Short‑term borrowings (2023‑01‑01): €444,100,000  
   - Current portion of long‑term borrowings (2023‑01‑01): €1,909,300,000  

   **Total debt** = €8,416,700,000 + €444,100,000 + €1,909,300,000 = **€10,770,100,000**

2. **Net debt** – subtract cash and short‑term liquid assets:
   - Cash & cash equivalents (2023‑01‑01): €2,155,100,000  
   - Current financial assets (short‑term investments): €255,300,000  

   **Net debt** = €10,770,100,000 − (€2,155,100,000 + €255,300,000) = **€8,359,700,000**

3. **EBITDA** – operating profit (EBIT) plus depreciation & amortisation:
   - Operating profit (Profit Loss From Operating Activities): €1,333,500,000  
   - Depreciation, amortisation and impairment (P&L): €725,700,000  

   **EBITDA** = €1,333,500,000 + €725,700,000 = **€2,059,200,000**

4. **Net Debt / EBITDA ratio** = €8,359,700,000 / €2,059,200,000 ≈ **4.06**

Thus, the estimated Net Debt / EBITDA ratio for 2022 is **4.06**.

<answer>4.06</answer>