To estimate the Funds From Operations (FFO) to Net Debt ratio for Terna S.p.A. at the end of 2022 based on standard S&P Global Ratings methodology:

1. **Calculate S&P Adjusted EBITDA and FFO:**
   - **Reported EBIT (Profit/Loss from Operating Activities):** €1,333.5 million
   - **Depreciation & Amortization (D&A):** €725.7 million
   - **Reported EBITDA:** €1,333.5 + €725.7 = €2,059.2 million

   - **Net Interest Expense:** Finance Costs (€121.8m) - Finance Income (€22.7m) = €99.1 million.
   - **Adjustments to Interest:** S&P adds back capitalized interest to reflect the total interest burden. Capitalized interest was €24.8 million. S&P also treats 50% of the hybrid bond coupon as interest (approx. €10.6 million).
   - **Adjusted Net Interest:** €99.1 + €24.8 + €10.6 = €134.5 million.
   - **Current Taxes:** Using cash taxes paid for the period gives a reliable proxy for S&P's FFO tax deduction = €380.1 million.

   - **S&P Adjusted FFO:** EBITDA (€2,059.2m) - Adjusted Net Interest (€134.5m) - Taxes Paid (€380.1m) = **€1,544.6 million**.
   *(Alternatively, using Net Income + D&A - Capitalized Interest - Hybrid Interest yields a very similar ~€1,548 million)*

2. **Calculate S&P Adjusted Net Debt:**
   - **Reported Gross Debt:** Long-term borrowings (€8,416.7m) + Current portion of long-term borrowings (€,1909.3m) + Short-term borrowings (€444.1m) = €10,770.1 million.
   - **Less Accessible Cash:** Cash and cash equivalents (€2,155.1m) and highly liquid Current Financial Assets (€255.3m).
   - **Reported Net Debt:** ~€8,359.7 million (Terna's formally reported Net Debt adjusting for specific derivative assets/liabilities comes to exactly €8,576 million). We will anchor to the reported €8,576 million baseline used by rating agencies. 
   - **S&P Debt Adjustments:**
     - **Hybrid Bonds:** Terna issued a €989 million perpetual green hybrid bond in 2022. S&P assigns this "intermediate equity content", treating it as 50% debt and 50% equity. Add €494.5 million to debt.
     - **Pensions:** Add unfunded pension deficits (Non-current provisions for employee benefits = €48.4 million).
   - **S&P Adjusted Net Debt:** €8,576m + €494.5m + €48.4m = **€9,118.9 million**.

3. **FFO to Net Debt Ratio:**
   - Ratio = €1,544.6 million / €9,118.9 million = 0.1694 (or ~17.0%)

<answer>0.17</answer>