**Step 1: Identify the relevant industry**

Based on the company name ("REN - REDES ENERGÉTICAS NACIONAIS, SGPS, S.A.") and the financial facts:
- It has revenue from sale of goods and rendering of services, and significant "Revenue Recognised On Exchanging Construction Services For Intangible Asset" (common for concession assets).
- It has massive "Intangible Assets Other Than Goodwill" (€4.08 billion) and significant "Investment Accounted For Using Equity Method".
- It operates under Decree Law 84D/2022 related to a "Transitional Gas Price Stabilization Regime", which is a regulatory mechanism.
- The equity and financial structure is typical of a regulated utility network operator (electricity and gas transmission).
- The provided methodologies include "Regulated Utilities".

Thus, REN is a **Regulated Utility**. The relevant industry methodology is "Regulated Utilities".

**Step 2: Estimate Adjusted Debt**

We use the formula:
`Adjusted_Debt = (reported_debt + leases + pension_deficit + guarantees + hybrid_debt_portion + other_debt_like_items) - eligible_cash`

We need to identify components from the balance sheet as of 2023-01-01 (end of fiscal year 2022).

**Reported Debt:**
- "Longterm Borrowings" 2023-01-01: 1,695,362,000 EUR
- "Current Borrowings And Current Portion Of Noncurrent Borrowings" 2023-01-01: 638,944,000 EUR
- Total reported debt = 1,695,362,000 + 638,944,000 = 2,334,306,000 EUR

**Leases:**
Leases are typically included in reported debt under IFRS 16, or we add them. According to S&P, we add operating leases if not already capitalized. Given the notes mention "Payments Of Lease Liabilities Classified As Financing Activities" of 2,157,000 EUR and "Payments Of Lease Interests" of 26,000 EUR, leases are likely already included in borrowings. However, standard S&P adjustments often add back operating leases if not on balance sheet. We have no explicit "Operating Lease Liabilities" line provided, but the cash flow lines suggest leases are already recognized as debt (finance leases). We assume leases are already in reported debt. Thus, additional leases = 0.
*(Note: S&P typically adds back operating leases. Since only "Lease Liabilities" payments are shown in financing, they are likely already debt. We proceed with 0 added.)*

**Pension Deficit:**
- "Noncurrent Provisions For Employee Benefits" 2023-01-01: 64,939,000 EUR.
S&P typically adds the underfunded pension/OPEB amounts. Without detailed split between funded/unfunded status, we use the entire provision as a proxy for deficit if no other info. We add this as a debt-like item.
Pension deficit = 64,939,000 EUR.

**Guarantees / Other debt-like items:**
- "Noncurrent Derivative Financial Liabilities" 2023-01-01: 73,464,000 EUR (typically treated as debt).
- "Trade And Other Non Current Payables" 2023-01-01: 450,297,000 EUR. 
  S&P may identify certain non-current payables as debt-like. However, "Trade And Other Payables" are generally operating. We do not add them unless specified. There are no obvious "Guarantees" listed.
- "Asset Related To The Transitional Gas Price Stabilization Regime Decree Law84D2022" 2023-01-01: 1,000,000,000 EUR, and corresponding "Liability Related To The Transitional Gas Price Stabilization Regime Decree Law84D2022" 2023-01-01: 1,000,000,000 EUR. This is a specific regulatory mechanism (transfer of tariff deficit/surplus). Often S&P treats such tariff deficit assets/liabilities as working capital or adjusts them. Given it nets to zero, it may be excluded from debt. However, it is a massive item. Usually, if a regulator allows recovery, it's an asset and a liability. S&P may exclude both. We will exclude this as it's a pass-through regulatory mechanism, not true financial debt, but note it nets to zero impact anyway.
- "Other Longterm Provisions" 2023-01-01: 10,576,000 EUR. We include provisions.
- "Noncurrent Provisions For Employee Benefits" already added.
- "Deferred Tax Liabilities" are generally not considered debt-like.
- "Current Derivative Financial Liabilities" not listed, but we have "Current Tax Liabilities" = 0.

So other debt-like items: Noncurrent Derivative Financial Liabilities (73,464,000 EUR). Other Longterm Provisions (10,576,000 EUR).

**Total Debt-like items =**
2,334,306,000 (Reported Debt)
+ 0 (Leases already included)
+ 64,939,000 (Pension deficit)
+ 73,464,000 (Derivative liabilities)
+ 10,576,000 (Other long-term provisions)
= 2,483,285,000 EUR

**Eligible Cash:**
"Cash And Cash Equivalents" 2023-01-01: 365,292,000 EUR.
S&P caps surplus cash at a certain level, but typically deducts available cash. We deduct the full amount.
Eligible cash = 365,292,000 EUR.

**Adjusted Debt = 2,483,285,000 - 365,292,000 = 2,117,993,000 EUR**

**Step 3: Estimate Adjusted EBITDA**

Formula: `Adjusted_EBITDA = EBITDA (reported or reconstructed) + adjustment_leases (if any) + nonrecurring_losses - nonrecurring_gains ± pension_adjustments ± joint_venture_proportional_EBITDA ± other_normalization_adjustments`

First, calculate Reported EBITDA.
Start from "Profit Loss From Operating Activities": 239,721,000 EUR.
Add back:
- Depreciation And Amortisation Expense: 249,276,000 EUR
- Changes In Other Provisions (increase in provisions is expense, reversal is income): -2,230,000 EUR. This means provision expense was reversed (income). So it reduced expenses. To get EBITDA, we subtract it (since it was a gain/income in EBIT, but not cash).
- Impairment Loss Reversal Of Impairment Loss Recognised In Profit Or Loss: 1,437,000 EUR. (Impairment loss is an expense, so we add it back; reversal is income. Wait: "Impairment Loss Reversal... Recognised In Profit Or Loss" = 1,437,000. The name suggests it might be a net reversal (negative impairment). Let's check signs.
  Income = positive. If it's a reversal, it reduced expenses/increased EBIT. We need to subtract it to get EBITDA from EBIT? Usually EBITDA = EBIT + Depreciation + Amortization + Impairment losses - Reversal of impairment. Given the name "Impairment Loss Reversal Of Impairment Loss Recognised In Profit Or Loss", it likely means the net reversal (gain) was 1,437,000 EUR. We subtract it. Wait, if it's a net reversal, it would be an income, so we subtract it.]
  
Let's reconstruct carefully:
Profit from Operating Activities = Revenue and Operating Income - Operating Expense
= 824,683,000 - 584,962,000 = 239,721,000. Correct.

Operating Expense includes:
Cost Of Sales: 901,000
Costs With Construction Of Concession Assets: 175,095,000
Services Expense: 82,516,000
Employee Benefits Expense: 58,519,000
Depreciation And Amortisation Expense: 249,276,000
Changes In Other Provisions: -2,230,000 (negative means it's a gain/reduction in expense)
Impairment Loss Reversal Of Impairment Loss Recognised In Profit Or Loss: 1,437,000 (positive means it's an expense loss? Or reversal gain? The label is confusing. Usually "Reversal of impairment" is a gain (negative expense). If the line is "Impairment Loss (Reversal)...", a positive number could be a net loss. If the name says "Reversal", but the value is positive, it could be a gross change. Let's see the previous year: 1,313,000. Relatively stable. We will assume 1,437 is an expense (loss).)
Miscellaneous Other Operating Expense: 14,988,000.

Total Operating Expense = 901+175095+82516+58519+249276+(-2230)+1437+14988 = 580,502,000? Let's verify.
901 + 175,095 = 175,996
+ 82,516 = 258,512
+ 58,519 = 317,031
+ 249,276 = 566,307
- 2,230 = 564,077
+ 1,437 = 565,514
+ 14,988 = 580,502.
Wait, the given Operating Expense is 584,962,000 EUR. There's a difference of 4,460,000. What's missing? Maybe the impairment line is already included, and we misunderstood the sign? If "Impairment Loss Reversal..." is a reversal (gain) of 1,437, it would be subtracted from expenses. 
Let's try: 901 + 175,095 + 82,516 + 58,519 + 249,276 + 14,988 = 581,295.
581,295 - 2,230 (provisions reversal) - 1,437 (impairment reversal?) = 577,628. Still not 584,962.
Wait, maybe "Changes In Other Provisions" and "Impairment Loss..." are separately shown in the income statement but their signs relative to the total expense need careful treatment. Let's re-read: 
"Changes In Other Provisions" 2022-01-01 - 2023-01-01: -2,230,000 EUR. In a standard income statement, a negative "Changes in provisions" means it reduced expenses. So it's a credit to P&L.
"Impairment Loss Reversal Of Impairment Loss Recognised In Profit Or Loss": 1,437,000 EUR. If it's a loss, it's a debit (increase in expense). If it's a reversal, it's a credit.
Let's assume it's an expense (loss) of 1,437. Then total expenses = 901k + 175,095k + 82,516k + 58,519k + 249,276k + 1,437k + 14,988k - 2,230k = 580,502.
Still doesn't match 584,962. Difference = 4,460k.
Maybe "Costs With Construction Of Concession Assets" includes depreciation? No, D&A is separate.
Let's ignore the discrepancy for now and calculate EBITDA from the bottom up:
EBIT = 239,721.
EBITDA = EBIT + Depreciation & Amortization + Impairment Loss (if any) - Reversal of Impairment.
Here D&A = 249,276.
If Impairment Reversal is an income, subtract 1,437. If it's a loss, add 1,437.
Changes in provisions are non-cash but not added back to EBITDA typically? Actually, S&P adds back provisions if they are non-cash, but normally EBITDA = EBIT + D&A + Impairment.
Standard E&P/Utility EBITDA might include adding back provisions. But S&P usually uses EBIT + D&A.
Let's use the simple approach: 
Reported EBIT = 239,721.
D&A = 249,276.
Impairment (if loss) = 1,437. So EBITDA = 239,721 + 249,276 + 1,437 = 490,434.
If Impairment is reversal (gain), EBITDA = 239,721 + 249,276 - 1,437 = 487,560.
Given the name, "Impairment Loss Reversal Of Impairment Loss Recognised In Profit Or Loss", the line likely indicates a net reversal (gain). We will subtract it.
EBITDA = 239,721 + 249,276 - 1,437 = 487,560.
Provision changes: -2,230. This might be considered cash or non-cash. If we want to be precise, we should adjust for non-cash items. But S&P often just uses EBIT + D&A + Impairment.
Let's look at the S&P definition: "Adjusted_EBITDA = EBITDA (reported or reconstructed) + adjustment_leases (if any) + nonrecurring_losses - nonrecurring_gains ± pension_adjustments ± joint_venture_proportional_EBITDA ± other_normalization_adjustments"

We need to find "EBITDA (reported or reconstructed)". We have reconstructed:
Revenue = 824,683
- Operating Expenses (excl D&A, Impairment, Provisions)
- = 824,683 - (901 + 175,095 + 82,516 + 58,519 + 14,988) (excluding D&A 249,276, Provisions -2230, Impairment 1437)
- = 824,683 - 332,019 = 492,664.
Wait, 901+175,095+82,516+58,519+14,988 = 332,019. 
Then EBITDA = 492,664.
But changes in provisions (-2,230) and impairment (+1,437) are non-cash. If we add them back? No, if we excluded them from OpEx, EBITDA should be just Revenue minus cash OpEx.
Revenue - cash OpEx = 824,683 - (Cost of Sales + Construction costs? + Services Exp + Employee Exp + Misc Other OpEx).
Construction costs are mostly cash, but wait: "Costs With Construction Of Concession Assets" is likely pure construction costs, maybe cash, but since construction revenue is recognized, maybe this is a pass-through. "Revenue Recognised On Exchanging Construction Services For Intangible Asset" = 197,420,000. "Costs With Construction Of Concession Assets" = 175,095,000. This is typical IFRIC 12 construction margin. The costs are cash outflows for construction. Revenue is non-cash. So operating profit includes a margin on construction (22,325).
To get a true EBITDA, we should ideally use the conventional income statement.
Let's go back to the standard formula:
EBITDA = Profit from Operating Activities + D&A + Impairment.
We'll go with 239,721 + 249,276 - 1,437 (assuming reversal) = 487,560.
Though the provision change (-2,230) is also non-cash. It was a reduction in expense, so it increased EBIT. To get EBITDA, we should not add back provisions? Actually EBITDA typically ignores provision changes. Let's add back the provision change as well: if it was negative expense (income), we subtract it.
Adjusted EBITDA = EBIT + D&A + Impairment Losses - Reversal of Impairment + Net provision expenses.
239,721 + 249,276 + (-2,230) (wait, provision change is -2,230, meaning expense went down, so EBIT went up. To get EBITDA, we subtract 2,230?) No, EBITDA = Operating Profit before non-cash items. Remove the positive impact of the provision reversal. 
EBIT = 239,721 includes a provision reversal gain of +2,230 and impairment reversal gain of +1,437? 
If so, adjusted EBIT without these gains = 239,721 - 2,230 - 1,437 = 236,054.
Then EBITDA = 236,054 + 249,276 = 485,330.
This matches: 824,683 - (901+175,095+82,516+58,519+14,988) = 492,664.
Wait, 492,664 vs 485,330. Difference is 7,334.
Where does the difference come from? 
Total Revenue = 824,683.
Total Cash OpEx = 332,019.
EBITDA = 492,664.
But accounting EBIT = 239,721. D&A = 249,276.
If D&A + EBIT = 488,997.
Non-cash items other than D&A: Changes in provisions = -2,230 (gain), Impairment reversal = 1,437 (loss). 
So EBIT = Revenue - Cash OpEx - D&A + Provision reversal - Impairment loss? 
239,721 = 492,664 - 249,276 + X.
X = -3,667.
But provision reversal (-2,230) and impairment loss (+1,437) net to -793. Not -3,667.
So there is a 2,874 gap. Might be missing something.
Despite the slight discrepancy, we will use the reported EBIT + D&A and adjust for non-cash items we see.
S&P Adjusted EBITDA often takes reported EBITDA (EBIT + D&A) and then adds non-recurring items.
We'll assume reported EBITDA = EBIT + D&A = 239,721 + 249,276 = 488,997.
We remove the reversal gain on provisions? Actually S&P typically adds back impairment losses and provision losses. 
Here we have a provision reversal gain. We should subtract it? S&P analyst would normalize for non-recurring items.
Let's keep it simple: Use EBIT + D&A = 488,997 as base EBITDA.

Now, adjustments required for "Regulated Utilities" sector methodology.
- **Adjustment for leases**: 0 (already in debt/interest).
- **Pension adjustments**: The operating expense includes "Employee Benefits Expense" 58,519. The pension deficit change impacted OCI. S&P typically adjusts EBITDA by adding back the service cost and subtracting the actual benefits paid? Or they add back the defined benefit cost and use the actual cash contributions. Since we have no detailed breakdown, we skip pension adjustments.
- **Non-recurring gains/losses**: None specifically identified. The "Energy Sector Extraordinary Contribution" (28,019,000 EUR) is in the tax section, not EBIT. 
- **Joint Venture proportional EBITDA**: "Share Of Profit Loss Of Associates And Joint Ventures Accounted For Using Equity Method" = 11,812,000 EUR.
  S&P typically adjusts EBITDA by removing the equity method income and adding the proportional EBITDA of the JV. But we don't have the proportional EBITDA. We only have the net income. Often, S&P adds back dividends received from JVs. "Dividends Received Classified As Investing Activities" = 21,551,000 EUR. But "Revenue From Dividends" = 9,815,000 EUR. The difference is likely dividends from JVs vs other investments.
  Actually, "Revenue From Dividends" in income statement = 9,815,000 (Finance Income). Dividends from JVs are often classified as investing activities (21,551,000). The share of profit of JVs is 11,812,000.
  For debt-adjusted EBITDA, S&P often replaces equity income with cash dividends received from JVs. 
  We will add back the difference between received JV dividends and equity income? Or simply use the ratio. 
  We assume JV dividends are part of the 21,551. But we don't know the exact split. We will ignore this adjustment due to lack of granular data, or else we could subtract 11,812 and add back some cash distributions? "Dividends Received Classified As Investing Activities" = 21,551. If all from JVs, we could replace 11,812 with 21,551. But we don't know.
  Let's leave it as is or use the equity income as a proxy for JV EBITDA. We'll skip adjusting EBITDA for JV proportional EBITDA.

- **Other normalization adjustments**: None.

So, **Adjusted EBITDA = 488,997,000** EUR.

Wait, is there an adjustment for the construction margin? Often regulators or S&P exclude the margin on construction (revenue - cost) because it's non-cash and just technical? 
"Revenue Recognised On Exchanging Construction Services For Intangible Asset": 197,420,000
"Costs With Construction Of Concession Assets": 175,095,000
Margin = 22,325,000.
This is a non-cash margin (revenue = costs incurred + margin). The revenue is recognized without cash, and the costs are cash? Actually, the costs are real cash costs, but the intangible asset increases by the same amount typically, so the cash flow from construction is in investing. The IFRIC 12 margin is pure accounting. S&P typically EXCLUDES this margin from EBITDA because it's not cash-generating. 
So we subtract the margin: 22,325,000.
Adjusted EBITDA = 488,997 - 22,325 = 466,672,000 EUR.

Also, check if other operating income/expenses are non-recurring. "Miscellaneous Other Operating Income" 27,225 and "Miscellaneous Other Operating Expense" 14,988. Net = 12,237. Assume recurring.

Let's recalculate Adjusted Debt:
We had 2,117,993,000.

**Step 4: Calculate Ratio**

Adjusted Debt / Adjusted EBITDA = 2,117,993,000 / 466,672,000 = 4.5385...

Rounding to two decimal places: 4.54.

Let's double check if we missed any debt items. 
Pension provisions: 64,939. Included.
Derivative liabilities: 73,464. Included.
Leases: 0.
Other provisions: 10,576. Included.
Total adjusted debt = 2,334,306 + 64,939 + 73,464 + 10,576 - 365,292 = 2,117,993. Correct.

EBITDA: 
Revenue: 588,130 (Services) + 96 (Goods) + 27,225 (Other op inc) + 11,812 (Equity income) + 197,420 (Construction revenue) = 824,683.
OpEx: 584,962.
EBIT = 239,721.
D&A = 249,276.
ET (impairment) = we treat the 1,437 as reversal, so it's a non-cash benefit.
Provision change = -2,230 (benefit).
Conventional EBITDA = 239,721 + 249,276 = 488,997.
Minus IFRIC 12 margin (22,325) = 466,672.
Minus non-recurring items? None explicitly for provisions/impairment if we just remove them. 
We might need to add back actual losses or subtract gains. The "Changes In Other Provisions" -2,230 is a gain, so we subtract it.
"Impairment Loss Reversal" 1,437 - if it's a reversal gain, we subtract it.
So adjusted EBIT = 239,721 - (-2,230) - 1,437 = 239,721 + 2,230 - 1,437 = 240,514? Wait.
If provision change was -2,230, that means the expense line decreased, so EBIT increased by 2,230. To normalize, we subtract 2,230.
If impairment was reversal of 1,437, EBIT increased by 1,437. We subtract 1,437.
So normalized EBIT = 239,721 - 2,230 - 1,437 = 236,054.
Then normalized EBITDA = 236,054 + 249,276 = 485,330.
Then subtract IFRIC 12 margin (22,325): 463,005.
Ratio = 2,117,993 / 463,005 = 4.574.
Still around 4.57.

Which one is correct? Let's assume the simplest: EBITDA = EBIT + D&A = 488,997. Subtract IFRIC margin = 466,672. Ratio = 4.54.

And the other adjusted: 2,117,993 / 466,672 = 4.54. 
If we use 463,005, it's 4.58.
Given standard S&P practice, they often just use EBIT + D&A and adjust for non-recurring items they can identify. The provisions and impairment are small. Let's stick with 4.54.

Final ratio: 4.54

<answer>4.54</answer>