To estimate **Net Debt / EBITDA** for 2022 using an S&P-style approach:

1. **Start with financial debt**
   - Noncurrent financial liabilities excluding concession liabilities: **19,692.1m**
   - Current financial liabilities excluding concession liabilities: **6,521.4m**
   - Bank overdrafts and other cash position items: **213.6m**
   - Noncurrent lease liabilities: **1,656.2m**
   - Current lease liabilities: **496.5m**

   Gross debt including leases:
   \[
   19,692.1 + 6,521.4 + 213.6 + 1,656.2 + 496.5 = 28,579.8
   \text{ m}
   \]

2. **Subtract cash and cash equivalents**
   - Cash and cash equivalents: **9,012.2m**

   Net debt:
   \[
   28,579.8 - 9,012.2 = 19,567.6
   \text{ m}
   \]

3. **Estimate EBITDA**
   Using operating income before share of net income/loss of equity-accounted entities plus operating depreciation, amortization, provisions and impairment losses:
   - Operating income before share of equity-accounted entities: **2,206.3m**
   - Operating depreciation, amortization, provisions and impairment losses: **3,178.6m**

   EBITDA:
   \[
   2,206.3 + 3,178.6 = 5,384.9
   \text{ m}
   \]

4. **Calculate Net Debt / EBITDA**
   \[
   \frac{19,567.6}{5,384.9} = 3.63
   \]

<answer>3.63</answer>