To estimate the Net Debt / EBITDA ratio for 2022 for REN - Redes Energéticas Nacionais, SGPS, S.A., we first identify the relevant components from the provided data for the fiscal year 2022 (ending 2023-01-01):

1.  **Debt calculation**: Under S&P methodology, Net Debt is generally defined as Total Debt (current and non-current borrowings) minus Cash and Cash Equivalents.
    *   Longterm Borrowings (2023-01-01): 1,695,362,000 EUR
    *   Current Borrowings and Current Portion of Non-current Borrowings (2023-01-01): 638,944,000 EUR
    *   Total Debt = 1,695,362,000 + 638,944,000 = 2,334,306,000 EUR
    *   Cash and Cash Equivalents (2023-01-01): 365,292,000 EUR
    *   Net Debt = 2,334,306,000 - 365,292,000 = 1,969,014,000 EUR

2.  **EBITDA calculation**: EBITDA is defined as Operating Profit + Depreciation and Amortisation.
    *   Profit/Loss from Operating Activities (2022-01-01 – 2023-01-01): 239,721,000 EUR
    *   Depreciation and Amortisation Expense (2022-01-01 – 2023-01-01): 249,276,000 EUR
    *   EBITDA = 239,721,000 + 249,276,000 = 488,997,000 EUR

3.  **Ratio calculation**:
    *   Net Debt / EBITDA = 1,969,014,000 / 488,997,000 ≈ 4.0266

(Note: S&P methodology sometimes adjusts for items like the Transitional Gas Price Stabilization Regime; however, using the provided financial statement items directly for the 2022 reporting period results in the following calculation.)

<answer>4.0266</answer>