Step 1 — Relevant industry  
HERA S.p.A. is a multi-utility group operating in regulated utility activities such as energy networks, water, and environmental services, with some market/exposed energy activities. The most relevant provided methodology is therefore Regulated Utilities.

Step 2 — Estimate Adjusted_Debt  

Baseline formula:

Adjusted_Debt = reported_debt + leases + pension_deficit + guarantees + hybrid_debt_portion + other_debt_like_items − eligible_cash

Using available 2022 year-end balance sheet data as of 2023-01-01:

Reported financial debt:
- Noncurrent financial liabilities = €5,689.9m
- Current financial liabilities = €650.1m

Reported financial debt = 5,689.9 + 650.1 = €6,340.0m

Lease liabilities:
- Noncurrent lease liabilities = €55.1m
- Current lease liabilities = €21.3m

Leases = 55.1 + 21.3 = €76.4m

Pension / employee benefit obligations:
- Noncurrent provisions for employee benefits = €92.0m

Pension-related debt-like item = €92.0m

Other debt-like items:
- Other long-term provisions = €565.6m  
These may include asset retirement, environmental, and risk provisions. For a conservative S&P-style estimate, include them as debt-like obligations.

Other debt-like items = €565.6m

Eligible cash:
- Cash and cash equivalents = €1,942.4m

No data is provided to haircut or restrict cash, so use reported cash as eligible cash.

Adjusted_Debt = 6,340.0 + 76.4 + 92.0 + 565.6 − 1,942.4  
Adjusted_Debt = €5,131.6m

Step 3 — Estimate Adjusted_EBITDA  

Reconstruct EBITDA from operating profit plus depreciation, amortization, and provisions.

Given:
- Profit/loss from operating activities = €533.8m
- Amortisation, depreciation and provisions = €667.1m

EBITDA proxy = 533.8 + 667.1 = €1,200.9m

However, the cash flow statement separates:
- Depreciation/amortisation/impairment = €478.6m
- Allocation to provisions = €188.5m

These total €667.1m, matching the income statement line. Since EBITDA normally adds back depreciation and amortization, but not all provisions necessarily qualify as EBITDA add-backs under S&P-style adjusted EBITDA, a more conservative and cleaner EBITDA estimate is:

Adjusted_EBITDA = Operating profit + depreciation/amortisation/impairment  
Adjusted_EBITDA = 533.8 + 478.6 = €1,012.4m

Lease EBITDA adjustment:
Lease expense is not separately disclosed. IFRS 16 leases are already reflected with depreciation/interest rather than rent expense, and lease liabilities are included in adjusted debt. No additional lease EBITDA adjustment is available.

Joint ventures:
Share of profit of associates/JVs = €10.0m, but proportional JV EBITDA is not disclosed. No adjustment made.

Nonrecurring items:
No clear nonrecurring losses/gains are identified from the facts. No adjustment made.

Adjusted_EBITDA = €1,012.4m

Step 4 — Calculate Adjusted_Debt / Adjusted_EBITDA

Adjusted_Debt / Adjusted_EBITDA = 5,131.6 / 1,012.4 = 5.0687

Rounded to two decimals = 5.07

<answer>5.07</answer>