To estimate the S&P-adjusted debt-to-EBITDA ratio for IBERDROLA SA for the year ended December 31, 2022, we follow the standard S&P Global Ratings methodology for corporate and regulated utility issuers. 

**Step 1: Estimate Adjusted EBITDA**
We start with the reported EBITDA and apply standard S&P adjustments, which primarily include removing non-recurring items and factoring in cash received from equity investments.
* **Reported EBITDA:** 13,228,000,000 EUR (Beneficio Bruto De Explotacion Ebitda)
* **Less: Nonrecurring gains:** -911,000,000 EUR (Other Gains Losses, typically treated as non-operating/non-recurring asset sales)
* **Plus: Dividends received from equity investments:** +67,000,000 EUR (as S&P typically adds cash dividends received from associates/JVs when proportional consolidation is not used; share of profit was 146m but is excluded from EBITDA)
* **Adjusted EBITDA** = 13,228,000,000 - 911,000,000 + 67,000,000 = **12,384,000,000 EUR**

**Step 2: Estimate Adjusted Debt**
We sum the reported financial debt and add standard debt-like adjustments (leases, pensions, and applicable hybrids), then subtract eligible cash and liquid investments.
* **Reported Debt (Bonds & Bank Debt):** 36,129,000,000 EUR (Noncurrent) + 10,458,000,000 EUR (Current) = 46,587,000,000 EUR
* **Plus: Leases:** 2,287,000,000 EUR (Noncurrent) + 151,000,000 EUR (Current) = 2,438,000,000 EUR
* **Plus: Pension Deficit:** 1,226,000,000 EUR (Noncurrent) + 42,000,000 EUR (Current) = 1,268,000,000 EUR 
* **Plus: Hybrid Capital Instruments (recorded in liabilities):** 576,000,000 EUR (Noncurrent) + 87,000,000 EUR (Current) = 663,000,000 EUR *(Note: Subordinated perpetual obligations recorded in equity are also typically adjusted by S&P at 50% equity/50% debt, but since the exact outstanding principal balance isn't detailed in the given line items, we rely cleanly on explicitly quantified liability instruments)*
* **Gross Adjusted Debt** = 46,587,000,000 + 2,438,000,000 + 1,268,000,000 + 663,000,000 = **50,956,000,000 EUR**

* **Less: Eligible Cash & Liquid Investments:** 
  * Cash and Cash Equivalents = 4,608,000,000 EUR
  * Other Current Financial Assets (highly liquid short-term investments) = 2,964,000,000 EUR
  * Total Eligible Cash = 7,572,000,000 EUR

* **Net Adjusted Debt** = 50,956,000,000 - 7,572,000,000 = **43,384,000,000 EUR**

**Step 3: Calculate the Ratio**
* **Adjusted Debt / Adjusted EBITDA** = 43,384,000,000 EUR / 12,384,000,000 EUR ≈ 3.503

<answer>3.50</answer>