**Step 1: Identify the relevant industry**
Based on the provided annual report facts, Hera S.p.A. operates in multi-utilities (providing electricity, gas, water, and waste management services). According to the S&P sector methodologies provided, it falls under the **Regulated Utilities** sector. 

**Step 2: Estimate Adjusted_Debt**
Following the S&P methodology for Regulated Utilities, Adjusted Debt includes reported debt, leases (which are debt-like), and other debt-like items, minus eligible cash. 
- **Reported Debt:** The reported financial liabilities consist of Noncurrent Financial Liabilities (5,689,900,000 EUR) and Current Financial Liabilities (650,100,000 EUR). 
  Reported Debt = 5,689,900,000 + 650,100,000 = 6,340,000,000 EUR.
- **Leases:** Under IFRS 16, Right-of-Use assets are capitalized on the balance sheet with corresponding lease liabilities. We include Noncurrent Lease Liabilities (55,100,000 EUR) and Current Lease Liabilities (21,300,000 EUR).
  Leases = 55,100,000 + 21,300,000 = 76,400,000 EUR.
- **Other debt-like items / Guarantees / Pension deficit / Hybrids:** None are explicitly disclosed in the given facts, so we assume 0 EUR.
- **Eligible Cash:** We deduct Cash And Cash Equivalents, which are 1,942,400,000 EUR.
  
*Calculation:*
Adjusted_Debt = Reported Debt + Leases - Eligible Cash
Adjusted_Debt = 6,340,000,000 + 76,400,000 - 1,942,400,000 = 4,474,000,000 EUR.

**Step 3: Estimate Adjusted_EBITDA**
Following the S&P methodology, we reconstruct EBITDA from the reported Profit Loss From Operating Activities by adding back D&A and adjusting for leases and other items.
- **EBITDA (Reconstructed):** Profit Loss From Operating Activities is 533,800,000 EUR. Amortisation Depreciation And Provisions reported in the income statement is 667,100,000 EUR. However, the Cash Flow Statement provides the specific "Adjustments For Depreciation And Amortisation Expense And Impairment Loss Reversal" which is 478,600,000 EUR. We use this specific D&A figure from the cash flow statement.
  EBITDA = Operating Profit + D&A = 533,800,000 + 478,600,000 = 1,012,400,000 EUR.
- **Adjustment for Leases:** Under the standard S&P ratios and adjustments methodology, the interest expense embedded in lease liabilities is added back to EBITDA to treat the operating leases as debt. The finance costs are 217,200,000 EUR and finance income is 82,200,000 EUR, yielding a net finance cost of 135,000,000 EUR. Based on the lease liabilities of ~76.4 million EUR and typical interest rates, the lease interest portion is estimated. A precise calculation from the provided line items shows finance costs excluding lease interest align with the average interest on financial debt (e.g. ~3.8% on ~6.34B = ~240M). Thus, lease interest is embedded in the net finance costs. Using S&P's standard rule of thumb (1/3 of lease liabilities as approximate annual rent/interest), 1/3 * 76,400,000 = ~25.5 million EUR. Alternatively, taking the difference between total finance costs (217.2M) and estimated interest on financial debt (~241M) suggests lease interest is broadly offset or accounted for. Given the difficulty to precisely isolate lease interest, we recognize the EBITDA is lifted by the lease interest add-back. We will add back the net finance cost related to leases. If we assume the full lease liabilities are treated as debt, we must adjust EBITDA by the lease interest (~25.5M).
  Adjusted EBITDA = 1,012,400,000 + 25,500,000 = 1,037,900,000 EUR.
- *(Note: for utilities, standard adjustments like proportional consolidation of JVs typically don't apply under S&P unless specifically instructed; the 10M EUR equity method income is immaterial and standard under S&P).*

**Step 4: Calculate Adjusted_Debt / Adjusted_EBITDA ratio**
*Calculation:*
Adjusted_Debt / Adjusted_EBITDA = 4,474,000,000 / 1,037,900,000 = 4.3111...

Rounding to two decimal places, we get 4.31.

<answer>4.31</answer>