To estimate the FFO (Funds From Operations) to Net Debt ratio for Naturgy Energy Group SA for 2022, we follow the standard S&P methodology:

**1. Calculate FFO (Funds From Operations):**
FFO is typically calculated as Cash Flow from Operating Activities adjusted for certain non-cash items and working capital changes.
*   **Cash Flow from Operating Activities (2022):** 4,242,000,000 EUR
*   **Adjustment for Change in Working Capital:** The "Increase Decrease In Working Capital" is -272,000,000 EUR. To derive FFO, we remove the impact of working capital: 4,242,000,000 - (-272,000,000) = 4,514,000,000 EUR.

**2. Calculate Net Debt:**
Net Debt is calculated as Total Financial Liabilities (Current + Noncurrent) minus Cash and Cash Equivalents.
*   **Noncurrent Financial Liabilities (2023-01-01 / end of 2022):** 13,999,000,000 EUR
*   **Current Financial Liabilities (2023-01-01 / end of 2022):** 2,302,000,000 EUR
*   **Total Financial Liabilities:** 13,999,000,000 + 2,302,000,000 = 16,301,000,000 EUR
*   **Less Cash and Cash Equivalents (2023-01-01):** 3,985,000,000 EUR
*   **Net Debt:** 16,301,000,000 - 3,985,000,000 = 12,316,000,000 EUR

**3. Calculate FFO / Net Debt Ratio:**
*   **FFO / Net Debt:** 4,514,000,000 / 12,316,000,000 ≈ 0.3665

(Note: S&P methodology often includes specific adjustments for lease liabilities, pensions, and hybrid instruments. Given the provided data, we use the core financial debt and the operational cash flow adjusted for working capital).

<answer>0.3665</answer>