I'll estimate the FFO / Net Debt ratio for ERG S.P.A. for 2022 based on S&P methodology.

## Step 1: Calculate FFO (Funds From Operations) - S&P Methodology

S&P's FFO starts with net income from continuing operations, adds back depreciation & amortization, and adjusts for non-cash items, deferred taxes, and other items. A simplified approach:

**FFO ≈ EBITDA - Net Interest Expense - Cash Taxes**

From the data for 2022 (period 2022-01-01 to 2023-01-01):

- **EBITDA** = 499,430,000 EUR
- **Net Finance Costs** = 36,573,000 EUR (Finance Income Cost is -36,573,000)
- **Cash Taxes Paid** = 91,854,000 EUR

However, S&P typically adjusts for operating leases. Let me also consider:
- Lease payments classified as financing: 8,337,000 EUR
- Interest paid classified as financing: 29,146,000 EUR

**FFO (S&P approach):**
FFO = EBITDA - Cash Interest Paid - Cash Taxes Paid
FFO = 499,430,000 - 29,146,000 - 91,854,000 = 378,430,000 EUR

But S&P also includes lease adjustments. Adding back lease depreciation (included in EBITDA already through operating lease treatment) and deducting lease interest. For simplicity with available data:

FFO ≈ 499,430,000 - 29,146,000 - 91,854,000 = 378,430,000 EUR

## Step 2: Calculate Net Debt - S&P Methodology

**Gross Debt** includes:
- Non-current financial liabilities at fair value: 0 EUR
- Other non-current financial liabilities: 1,751,255,000 EUR
- Non-current lease liabilities: 150,955,000 EUR
- Current financial liabilities at fair value: 76,644,000 EUR
- Other current financial liabilities: 389,716,000 EUR
- Current lease liabilities: 6,362,000 EUR

**Total Gross Debt** = 0 + 1,751,255,000 + 150,955,000 + 76,644,000 + 389,716,000 + 6,362,000 = 2,374,932,000 EUR

**Cash & Cash Equivalents** = 392,811,000 EUR

S&P typically doesn't net all cash. They may consider surplus cash. However, for this estimate:

**Net Debt** = 2,374,932,000 - 392,811,000 = 1,982,121,000 EUR

However, S&P might also consider some of the current financial assets. Let me use a more conservative approach and just use the straightforward calculation.

Actually, S&P often excludes derivatives from debt. The current financial liabilities at fair value (76,644,000) could be derivative liabilities. Let me exclude those and also exclude the non-current ones (already 0):

**Adjusted Gross Debt** = 1,751,255,000 + 389,716,000 + 150,955,000 + 6,362,000 = 2,298,288,000 EUR

**Net Debt** = 2,298,288,000 - 392,811,000 = 1,905,477,000 EUR

## Step 3: Calculate FFO / Net Debt

FFO / Net Debt = 378,430,000 / 1,905,477,000 ≈ 0.1986 or ~19.9%

Alternatively with the broader debt definition:
FFO / Net Debt = 378,430,000 / 1,982,121,000 ≈ 0.191 or ~19.1%

Taking the middle ground estimate:

<answer>0.20</answer>