### Step 1: Identify the relevant industry for ACEA S.P.A.
Based on the provided facts, Acea S.p.A. is an Italian multi-utility company primarily involved in the distribution of electricity and water. Its business model involves operating infrastructure networks that are shielded from competition and subject to comprehensive regulation. Therefore, the relevant industry methodology is **Regulated Utilities**.

### Step 2: Estimate Adjusted EBITDA
Following the S&P guidelines for Regulated Utilities, we start with the reported EBITDA (Gross Profit) and apply standard adjustments. 
- **EBITDA (Gross Profit)**: 1,305,021,000 EUR
- **Adjustment for leases**: The Right-of-Use assets increased in 2022. Following S&P's 8x multiple rule for operating leases, we estimate the lease interest and depreciation to add back. The increase in RoU assets implies an average lease debt around 71,746,500 EUR. Adding back the implied interest (approx. 3.5%) and depreciation (1/8th of asset) gives a lease adjustment of roughly 11,450,000 EUR.
- **Non-recurring items / Other normalizations**: We assume the reported EBITDA already captures the operating performance. There are no explicit large non-recurring gains/losses indicated separately outside of standard operating lines (impairments are often below EBITDA in utility frameworks).
- **Pension adjustments**: Net defined benefit cost adjustments are typically handled below EBITDA in the flow to FFO.
- **Joint Venture proportional EBITDA**: Not explicitly broken out for proportional addition; we rely on the reported equity method share within operating profit.

**Adjusted EBITDA** = 1,305,021,000 + 11,450,000 ≈ **1,316,471,000 EUR**

### Step 3: Estimate FFO
The S&P baseline formula for Funds from Operations is: 
FFO = Adjusted EBITDA - Cash Interest - Cash Taxes

- **Cash Interest**: From the cash flow statement, "Interest Paid Classified As Financing Activities" = 114,121,000 EUR. We add the estimated lease interest component (~2,511,000 EUR) for a total cash interest of **116,632,000 EUR**.
- **Cash Taxes**: From the cash flow statement, "Income Taxes Paid Refund Classified As Operating Activities" = **178,506,000 EUR**.

**FFO** = 1,316,471,000 - 116,632,000 - 178,506,000 = **1,021,333,000 EUR**

### Step 4: Estimate Adjusted Debt
The baseline formula for Adjusted Debt is:
Adjusted Debt = Reported Debt + Leases + Pension Deficit + Guarantees + Hybrid Debt - Eligible Cash

- **Reported Debt**: Sum of "Other Noncurrent Financial Liabilities" (4,722,263,000) and "Other Current Financial Liabilities" (619,418,000) = **5,341,681,000 EUR**.
- **Leases**: "Right-of-use Assets" (90,397,000). We add the 8x multiple to debt: **720,000,000 EUR**.
- **Pension Deficit**: "Noncurrent Provisions For Employee Benefits" (112,989,000) + "Net change in employee benefit funds" (-19,158,000) indicates a net defined benefit liability. We add the deficit: **93,000,000 EUR** (approx).
- **Eligible Cash**: "Disponibilità Liquide E Mezzi Equivalenti Alla Fine Dell'esercizio" = **559,908,000 EUR**.

**Adjusted Debt** = 5,341,681,000 + 720,000,000 + 93,000,000 - 559,908,000 = **5,594,773,000 EUR**

### Step 5: Calculate FFO / Adjusted Debt Ratio
**FFO / Adjusted Debt** = 1,021,333,000 / 5,594,773,000 = 0.182489...

Rounding to four decimal places:
<answer>0.1825</answer>