Step 1: Identify the relevant industry
Based on the facts provided, "ENI S.P.A." is a major integrated energy company with significant operations in oil and gas exploration and production, as well as unregulated power and gas. The S&P methodologies provided that best fit ENI are "Oil And Gas Exploration And Production" and "Unregulated Power And Gas". For a large integrated oil and gas company like Eni, the primary industry methodology is "Oil And Gas Exploration And Production". There are no specific industry adjustments in the O&G methodology that alter the baseline formulas for Adjusted EBITDA, FFO, or Adjusted Debt; it primarily relies on the standard corporate baseline formulas with generic adjustments.

Step 2: Estimate the "Adjusted_EBITDA"
Baseline formula: Adjusted_EBITDA = EBITDA (reported or reconstructed) + adjustment_leases + nonrecurring_losses - nonrecurring_gains ± pension_adjustments ± joint_venture_proportional_EBITDA ± other_normalization_adjustments

From the income statement data for 2022:
- Profit Loss From Operating Activities: 17,510,000,000 EUR
- Depreciation And Amortisation Expense: 7,205,000,000 EUR
- Impairment Loss Reversal Of Impairment Loss Recognised In Profit Or Loss: 1,140,000,000 EUR
- Write Off Of Tangible And Intangible Assets: 599,000,000 EUR

EBITDA = Operating Profit + Depreciation & Amortisation = 17,510,000,000 + 7,205,000,000 = 24,715,000,000 EUR.

Adjustments:
- adjustment_leases: S&P adds back an estimate of lease interest and depreciation. However, without specific lease interest data clearly separated from the 9,333,000,000 EUR finance costs, and following the baseline typically where EBITDA is formed before interest, the exact lease adjustment to EBITDA isn't explicitly calculable. We will use the reported EBITDA of 24,715,000,000 EUR.
- nonrecurring_losses - nonrecurring_gains: Impairments and write-offs are already included in the operating profit before our D&A add-back. (17,510M operating profit already includes the -1,140M reversal and -599M write-off). No additional adjustment needed here.
- pension_adjustments: None explicitly stated.
- joint_venture_proportional_EBITDA: Share of Profit Loss Of Equity Accounted Investments is 1,841,000,000 EUR. Since proportional EBITDA isn't given, we typically don't gross up without a margin assumption.
- other_normalization_adjustments: None explicitly stated.

Adjusted_EBITDA = 24,715,000,000 EUR.

Step 3: Estimate the "FFO"
Baseline formula: FFO = Adjusted_EBITDA - cash_interest - cash_taxes

From the cash flow statement data for 2022:
- Interest Paid Classified As Operating Activities: 851,000,000 EUR
- Income Taxes Paid Refund Classified As Operating Activities: 8,488,000,000 EUR

FFO = 24,715,000,000 - 851,000,000 - 8,488,000,000 = 15,376,000,000 EUR.

Step 4: Estimate the "Adjusted_Debt"
Baseline formula: Adjusted_Debt = (reported_debt + leases + pension_deficit + guarantees + hybrid_debt_portion + other_debt_like_items) - eligible_cash

From the balance sheet data as of 2023-01-01 (end of 2022):
- Shortterm Borrowings: 4,446,000,000 EUR
- Current Portion Of Longterm Borrowings: 3,097,000,000 EUR
- Longterm Borrowings: 19,374,000,000 EUR
Reported Debt = 4,446,000,000 + 3,097,000,000 + 19,374,000,000 = 26,917,000,000 EUR.

- leases: Current Lease Liabilities = 884,000,000 EUR; Noncurrent Lease Liabilities = 4,067,000,000 EUR. Total leases = 4,951,000,000 EUR.
- pension_deficit: Other Longterm Provisions (15,267M) and Noncurrent Provisions For Employee Benefits (786M) are present, but specific pension deficits aren't detailed; we won't assume an arbitrary deficit.
- hybrid_debt_portion: The equity statement shows "Decrease Through Coupon Payment On Perpetual Subordinated Bonds Equity" (138M) and "Increase Decrease Through Net Issue Reimbursement Of Perpetual Subordinated Bonds Equity" in prior years. S&P typically classifies deeply subordinated perpetual bonds as equity if there is no maturity and dividend push features, but absent exact terms, standard treatment usually starts at 0% equity credit if not specified, or full debt. Given it is classified in equity, we leave it out of adjusted debt unless required. 
- eligible_cash: Cash And Cash Equivalents = 10,155,000,000 EUR.

Adjusted_Debt = (26,917,000,000 + 4,951,000,000) - 10,155,000,000 = 21,713,000,000 EUR.

Step 5: Calculate the "FFO / Adjusted_Debt" ratio
FFO / Adjusted_Debt = 15,376,000,000 / 21,713,000,000 = 0.7081446...

Rounding to four decimal places: 0.7081

<answer>0.7081</answer>