To estimate the Funds From Operations (FFO) to Net Debt ratio for Italgas S.p.A. for 2022 (covering the period 2022-01-01 to 2023-01-01) according to standard S&P methodology, we perform the following calculations:

**1. Calculate FFO:**
S&P typically defines FFO as Cash Flow from Operations (CFO) adjusted for changes in working capital and certain non-cash items.
*   **Cash Flow from Operations (2022-2023):** 548,169,000 EUR
*   **Working Capital Adjustment:** The report provides an "Increase Decrease In Working Capital" for 2022-2023 of -336,750,000 EUR. 
*   **FFO Formula:** CFO - (Increase/Decrease in Working Capital) = 548,169,000 - (-336,750,000) = 884,919,000 EUR.

**2. Calculate Net Debt:**
Net Debt is generally defined as total short-term and long-term financial debt minus cash and cash equivalents.
*   **Short-term Financial Liabilities:** 142,437,000 EUR (excluding other current financial liabilities) + 290,000 EUR (other current financial liabilities) = 142,727,000 EUR.
*   **Long-term Financial Liabilities:** 6,402,913,000 EUR (excluding other non-current) + 34,000 EUR (other non-current financial liabilities) = 6,402,947,000 EUR.
*   **Total Financial Debt:** 142,727,000 + 6,402,947,000 = 6,545,674,000 EUR.
*   **Cash and Cash Equivalents (2023-01-01):** 451,946,000 EUR.
*   **Net Debt:** 6,545,674,000 - 451,946,000 = 6,093,728,000 EUR.

**3. Ratio Calculation:**
*   **FFO / Net Debt:** 884,919,000 / 6,093,728,000 ≈ 0.145217...

Rounding the result as a standard ratio:

<answer>0.1452</answer>