To estimate the FFO / Net Debt ratio for ENI S.P.A. for the year 2022 based on S&P methodology, we need to calculate Funds From Operations (FFO) and Net Debt.

**1. Calculate Funds From Operations (FFO)**

According to S&P Global Ratings methodology, FFO is generally calculated as:
$$FFO = \text{Net Income} + \text{Depreciation and Amortization} + \text{Other Non-Cash Items} + \text{Changes in Working Capital (sometimes excluded or adjusted, but standard FFO often starts with Net Income + D&A)}$$

A more precise S&P definition often used is:
$$FFO = \text{Net Income attributable to parent} + \text{Depreciation and Amortization} + \text{Deferred Taxes} + \text{Other non-cash items} - \text{Non-cash revenues}$$

However, a common simplified proxy for industrial companies like Eni, when detailed cash flow adjustments aren't fully broken down into "non-cash" vs "cash" components in the summary, is:
$$FFO \approx \text{Net Income} + \text{Depreciation & Amortization}$$

Let's look at the provided data for the period 2022-01-01 to 2023-01-01 (which represents the fiscal year 2022):
*   **Profit Loss Attributable To Owners Of Parent (Net Income):** 13,887,000,000 EUR
*   **Depreciation And Amortisation Expense:** 7,205,000,000 EUR

There are other non-cash items mentioned:
*   **Impairment Loss Reversal... Recognised In Profit Or Loss:** 1,140,000,000 EUR (This is a gain/reversal, so it reduces the expense or adds to income, but since it's included in Net Income, we need to check if it's non-cash. Impairment reversals are non-cash. Since it increased Net Income, we should subtract it if we are adding back non-cash expenses, or simply treat it as part of the non-cash adjustment. Standard FFO adds back depreciation and impairment losses. A reversal is a negative impairment loss. So we add back D&A (7,205) and subtract the reversal (1,140) because the reversal boosted NI but didn't provide cash? Actually, S&P FFO usually adds back *impairment charges*. A reversal is a credit. So $FFO = NI + D\&A - \text{Impairment Reversals} + \text{Impairment Charges}$. Here we have a net reversal of 1,140. So we subtract 1,140.
*   **Share Of Profit Loss Of Equity Accounted Investments:** 1,841,000,000 EUR. This is included in Net Income. The cash received is dividends. The difference between equity income and dividends is a non-cash item.
    *   Dividends Received Classified As Operating Activities: 1,545,000,000 EUR.
    *   Equity Income: 1,841,000,000 EUR.
    *   Non-cash portion = $1,841 - 1,545 = 296$ million. This amount is included in NI but not cash. So we subtract 296 million.
*   **Gains/Losses on disposals:** "Adjustments For Losses Gains On Disposal Of Noncurrent Assets" is -524,000,000 EUR. This implies a net gain of 524 million was included in NI. Gains on disposals are non-operating/non-cash from an operating perspective (investing activity). We should subtract this gain from NI to get FFO.

Let's refine the FFO calculation:
$$FFO = \text{Net Income} + \text{Depreciation \& Amortization} - \text{Impairment Reversals} - \text{Gain on Disposals} - (\text{Equity Income} - \text{Dividends from Equity})$$

*   Net Income: 13,887
*   + D&A: 7,205
*   - Impairment Reversal: 1,140 (The line item is "Impairment Loss Reversal... 1,140". A positive number here likely means a net reversal gain. If it were a charge, it would be an expense. The label says "Reversal", and the value is positive. In the P&L, this would increase profit. To get to cash flow from ops, we remove this non-cash gain.)
*   - Gain on Disposal: 524 (The adjustment is -524, meaning the P&L had a gain of 524. We subtract gains.)
*   - Undistributed Equity Income: $1,841 (\text{Equity Income}) - 1,545 (\text{Divs Received}) = 296$. We subtract the non-cash portion.

$$FFO = 13,887 + 7,205 - 1,140 - 524 - 296 = 19,132 \text{ million EUR}$$

Alternatively, a simpler S&P proxy often used is just $NI + D\&A$.
$13,887 + 7,205 = 21,092$.
Let's check "Cash Flows From Used In Operating Activities": 17,460.
CFO includes changes in working capital and taxes paid. FFO is a pre-working capital metric usually.
S&P defines FFO as net income plus depreciation, amortization, and other non-cash items.
Let's stick to the adjusted figure: **19,132 million EUR**.

*Self-Correction/Refinement:* Often, for quick estimation, "EBITDA - Taxes - Interest + Non-controlling interests" is not FFO. FFO is closer to CFO before working capital changes.
Let's look at the Cash Flow statement indirect method components provided:
Net Income (Attrib to Parent): 13,887
+ D&A: 7,205
+ Impairment (Net): The line is "Impairment Loss Reversal... 1,140". If this is a reversal, it's a negative expense. So we subtract it.
+ Undistributed profits of equity investments: The line "Adjustments For Undistributed Profits..." is 1,841. This suggests the entire equity income is added back? No, usually you add back the equity income and subtract dividends received. Or you subtract the undistributed portion. The line item "Adjustments For Undistributed Profits Of Investments Accounted For Using Equity Method" has a value of 1,841. This matches the "Share Of Profit Loss Of Equity Accounted Investments" (1,841). This implies the adjustment adds back the *entire* equity income? If so, then we must subtract dividends received separately?
Let's look at the CFO calculation in the text:
"Cash Flows From Used In Operating Activities" = 17,460.
Reconciliation:
Profit Loss: 13,961 (Total, not just parent). Let's use Total Profit Loss for a consolidated view if possible, but FFO is often attributed to parent. S&P usually uses consolidated net income including non-controlling interests for the numerator if the denominator is consolidated debt, or adjusts. Let's use the Total Profit Loss: 13,961.
Adjustments:
+ D&A: 7,205
+ Impairment: 1,140 (Wait, if it's a reversal, why is it added? Usually, impairments are added back. Reversals are subtracted. If the label is "Impairment Loss Reversal... 1,140", and it's in the adjustments list, does it mean the *net* adjustment was +1,140? Or is the line item name describing the *type* and the value is the amount? In 2021, the value was 167. In 2020, 3,183. These are likely net impairment charges (expenses). If they were reversals, they would reduce income. The label "Impairment Loss Reversal Of Impairment Loss Recognised In Profit Or Loss" is a standard XBRL tag that can represent both charges (positive expense) and reversals (negative expense). Given the magnitude and the nature of Oil & Gas, these are likely net impairment *charges* (expenses) that are added back. Let's assume 1,140 is an expense added back.
+ Undistributed profits equity method: 1,841. This is added back. This means the equity income (1,841) is removed from Net Income.
+ Losses/Gains on disposal: -524. This is a gain, so it's subtracted.
+ Dividend Income: 351. This is likely dividend income from financial assets (not equity method). It's added back? No, usually dividend income is investing. If it's in operating income, it's subtracted. The adjustment is positive 351? "Adjustments For Dividend Income" 351. If it's added back, it means it was deducted from NI? Or does it mean the cash flow is higher? Usually, you subtract dividend income from NI to get FFO/CFO if it's classified as investing. If the adjustment is positive, it might mean the income was *not* in NI? Unlikely. Let's assume standard: Subtract dividend income from NI. If the adjustment line is positive, it might be reversing a deduction? Let's look at Interest.
+ Interest Expense: 1,033. Added back.
+ Income Tax Expense: 8,088. Added back.
+ Other Adjustments: -2,773.
= Cash from Ops before Working Capital?
Sum: $13,961 + 7,205 + 1,140 + 1,841 - 524 + 351 + 159 (\text{Int Inc}) + 1,033 + 8,088 - 2,773 = 30,481$.
Then Working Capital changes: 1,279.
Then Interest/Tax paid adjustments?
The final CFO is 17,460.
The difference between 30,481 and 17,460 is huge.
Actually, S&P FFO is typically:
$FFO = \text{Net Income} + \text{Depreciation} + \text{Amortization} + \text{Impairment Charges} - \text{Impairment Reversals} - \text{Gains on Asset Sales} + \text{Losses on Asset Sales}$.
It generally does *not* add back interest and taxes (that's EBITDA). FFO is after interest and taxes.

So, let's restart the FFO calculation using the standard definition:
**FFO = Net Income (Attributable to Parent) + Depreciation & Amortization + Net Impairment Charges - Gains on Disposals + Losses on Disposals - Undistributed Equity Income (or add back Equity Income and subtract Divs Received)**

Using Attributable to Owners of Parent (13,887):
1.  **Net Income:** 13,887
2.  **Add D&A:** 7,205
3.  **Impairment:** The line "Impairment Loss Reversal... 1,140". In 2020, it was 3,183. In 2021, 167. These are likely net charges. If they were reversals, they would be gains. Given the industry volatility, large impairments are common. Let's assume 1,140 is a net charge added back.
4.  **Equity Income:** The line "Adjustments For Undistributed Profits... 1,841" suggests the full equity income is added back (removed from NI). To get FFO, we should include the *cash* dividends received from these entities. Dividends Received (Operating) = 1,545. However, some dividends might be classified as investing. The line "Dividends Received Classified As Operating Activities" is 1,545. So we add back the non-cash equity income (1,841) and then... wait.
    Standard FFO: Start with NI. Add back D&A. Add back Impairment.
    Equity Method: NI includes 1,841 income. Cash flow includes 1,545 dividends (if operating).
    If we define FFO as cash generating capability, we want the cash dividends.
    So: $NI - 1,841 (\text{remove equity income}) + 1,545 (\text{add cash divs})$. Net adjustment: $-296$.
    Alternatively, using the "Adjustments" line: If the cash flow statement adds back 1,841, it removes the accrual income. Then the cash inflow of 1,545 appears in CFO.
    For FFO, we usually just take NI + D&A + Impairment. We don't typically adjust for equity method differences unless specified, OR we treat the equity income as non-cash and subtract it, then add dividends.
    Let's stick to the core: $NI + D\&A + \text{Impairment}$.
5.  **Gains on Disposal:** "Adjustments For Losses Gains On Disposal... -524". This indicates a gain of 524 was in NI. We subtract it.
6.  **Other Non-Cash:** "Other Adjustments To Reconcile Profit Loss" -2,773. This is a large negative number. It likely includes changes in provisions, deferred taxes, etc., that are non-cash or working capital related. S&P FFO usually includes deferred taxes.
    Deferred Tax Assets/Liabilities change:
    Net Deferred Tax Assets 2023: 4,569; 2022: 2,713. Increase of 1,856 (Use of cash / Source of income?).
    Net Deferred Tax Liabilities 2023: 5,094; 2022: 4,835. Increase of 259.
    Net Deferred Tax Expense/Benefit?
    Income Tax Expense: 8,088.
    Current Tax Paid: 8,488.
    This is getting complex.

Let's use a simpler, robust S&P proxy often accepted for such estimates when detailed breakdowns are ambiguous:
**FFO ≈ Net Income + Depreciation & Amortization**
$FFO = 13,887 + 7,205 = 21,092$ million EUR.

Let's try to refine with the explicit "Non-cash" items identified in the Cash Flow from Operations section if possible.
S&P FFO = Net Income + Depreciation + Amortization + Impairment Charges - Impairment Reversals - Gains on Asset Sales + Losses on Asset Sales +/- Other Non-Cash Items (like deferred taxes, stock-based comp).
*   Net Income (Parent): 13,887
*   D&A: 7,205
*   Impairment: +1,140 (Assuming charge)
*   Gain on Disposal: -524
*   Equity Income Adjustment: The equity income (1,841) is non-cash. The cash received is 1,545. So we subtract the difference (296). Or, subtract full 1,841 and add 1,545. Net -296.
*   Stock-based comp: "Increase Decrease Through Sharebased Payment Transactions" 18. This is a non-cash expense included in NI? Yes. Add back 18.
*   Deferred Taxes: The tax expense is 8,088. The tax paid is 8,488. The difference is roughly covered by the change in deferred tax assets/liabilities and current tax liabilities.
    Change in Current Tax Liab: $(2,108 + 253) - (648 + 374) = 2,361 - 1,022 = 1,339$ increase.
    Change in Deferred Tax Assets: $4,569 - 2,713 = 1,856$ increase (Asset increase = expense > cash? No, Asset increase means we paid less cash than expense? Or we recognized expense but didn't pay? Increase in DTA is a source of cash relative to expense? No. Expense reduces NI. If DTA increases, it means Tax Expense < Tax Payable? No.
    Let's look at the "Adjustments For Income Tax Expense" in the cash flow: 8,088. This adds back the full tax expense. Then "Income Taxes Paid" subtracts 8,488.
    FFO is generally *after* tax. So we do NOT add back tax expense. We use Net Income (which is after tax).
    So, we do not adjust for taxes unless we are calculating Pre-Tax FFO (which S&P doesn't; they use after-tax).

So, refined FFO:
$13,887 (\text{NI}) + 7,205 (\text{D\&A}) + 1,140 (\text{Impairment}) - 524 (\text{Gain Disp}) - 296 (\text{Equity Diff}) + 18 (\text{SBC}) = 21,430$ million EUR.

Let's check if "Impairment" is a charge or reversal. The tag is "Impairment Loss Reversal...". In XBRL, if it's a reversal, it's often negative in the P&L (income). If the value provided is positive 1,140, it might be the absolute value of a reversal. If it's a reversal, it *increased* NI. Since it's non-cash (or rather, a write-up), we should *subtract* it from NI to get cash flow.
However, in 2020, the value was 3,183. Eni had significant impairments in 2020 due to the pandemic/oil crash. Those were charges. Charges are expenses (reduce NI). To get FFO, we add them back.
In 2022, oil prices were high. Impairments were likely low or reversals occurred.
If 1,140 is a reversal (gain), we subtract it.
If 1,140 is a charge (expense), we add it.
Given the tag "Impairment Loss Reversal Of Impairment Loss Recognised In Profit Or Loss", and the context of 2022 (high prices), it is highly probable these are **reversals** or net gains.
If it is a reversal, it is included in NI. We must subtract it.
Revised FFO:
$13,887 + 7,205 - 1,140 (\text{Rev}) - 524 (\text{Gain}) - 296 (\text{Equity}) + 18 (\text{SBC}) = 19,150$ million EUR.

Let's assume the conservative S&P FFO is around **19,150 - 21,000 million EUR**.
Let's use **20,000 million EUR** as a round estimate or stick to the calculated **19,150**.
Actually, S&P often includes "Preferred Dividends" in the deduction, but Eni doesn't seem to have them (only "Perpetual Subordinated Bonds" which might be equity or debt). The "Decrease Through Coupon Payment On Perpetual Subordinated Bonds Equity" is 138. If these are classified as equity, the coupon is a distribution of equity, not an expense in NI? Or is it an expense? "Coupon Payment... Equity" suggests they are treated as equity instruments. If they are equity, the coupon is not in Net Income (it's a distribution). So NI is already after-interest for debt but before-equity-distributions. FFO is available to all capital providers? No, FFO is usually attributable to parent shareholders.
If the perpetuables are equity, the 138 payment is not in NI.
If they are debt, the interest is in NI (as finance cost).
The line "Longterm Borrowings" does not explicitly list perpetuables. "Equity" section lists "Perpetual Subordinated Bonds Equity". So they are equity.
Therefore, the 138 coupon is not in Net Income.
FFO is cash flow from operations available to service debt.
S&P FFO = Net Income + D&A + ...
If the perpetuables are equity, we don't adjust NI for their coupons.

**2. Calculate Net Debt**

Net Debt = Total Debt - Cash and Cash Equivalents.

**Total Debt:**
We need to identify interest-bearing debt.
*   Short-term Borrowings: 4,446
*   Current Portion of Long-term Borrowings: 3,097
*   Long-term Borrowings: 19,374
*   Current Lease Liabilities: 884
*   Noncurrent Lease Liabilities: 4,067
*   Perpetual Subordinated Bonds: These are classified as Equity ("Perpetual Subordinated Bonds Equity"). S&P typically treats perpetuables as debt if they have mandatory coupons or are deeply subordinated but effectively debt-like. However, if classified as equity, S&P might still treat them as debt for leverage ratios (Debt/EBITDA). For Net Debt, it depends. S&P often includes perpetuables in debt if they are "debt-like". Given the name "Subordinated Bonds", they are likely debt-like. However, the prompt classifies them as Equity. Let's look at the "Finance Costs". Finance Costs are 9,333. This likely includes interest on borrowings and coupons on perpetuables.
    Standard Net Debt usually includes Borrowings + Lease Liabilities.
    Let's sum the explicit borrowings and leases:
    Short-term Borrowings: 4,446
    Current LT Borrowings: 3,097
    Long-term Borrowings: 19,374
    Current Leases: 884
    Noncurrent Leases: 4,067
    
    Total Gross Debt = $4,446 + 3,097 + 19,374 + 884 + 4,067 = 31,868$ million EUR.

    Should we include Perpetuals?
    The "Decrease Through Coupon Payment... 138" suggests an outstanding balance. We don't have the balance sheet line item for the principal of perpetuables in the "Liabilities" section, they are in Equity.
    S&P methodology: "Debt includes... perpetual debt securities... if they are rated as debt or treated as debt by the agency."
    Without the principal amount, we can't easily add them. However, looking at "Equity", the perpetuables are part of equity.
    Let's check if "Other Noncurrent Liabilities" or similar contains them. No, they are in Equity.
    If we exclude them, Net Debt is lower. If we include them, Net Debt is higher.
    Given the explicit classification as Equity in the provided facts, and lack of principal value, we will exclude them from the *calculated* Net Debt, or assume they are negligible or included in "Other". But "Perpetual Subordinated Bonds" are usually significant.
    Let's look at the change in Equity.
    Actually, let's stick to the explicit Borrowings and Leases which are clearly debt.
    Gross Debt = 31,868 million EUR.

**Cash and Cash Equivalents:**
*   Cash And Cash Equivalents 2023-01-01: 10,155 million EUR.
    (Note: The prompt asks for 2022 ratio. The data "2023-01-01" is the ending balance for the 2022 fiscal year. So we use the 2023-01-01 balance sheet values for the denominator).

Net Debt = Gross Debt - Cash
Net Debt = $31,868 - 10,155 = 21,713$ million EUR.

**3. Calculate Ratio**

FFO / Net Debt
Using FFO ≈ 19,150 million EUR (Adjusted for reversals/gains)
Ratio = $19,150 / 21,713 \approx 0.88$

Using FFO ≈ 21,092 million EUR (Simple NI + D&A)
Ratio = $21,092 / 21,713 \approx 0.97$

S&P FFO typically adds back impairments. If the 1,140 is a charge (add back), FFO is higher. If it's a reversal (subtract), FFO is lower.
In 2022, Eni reported strong earnings. Impairment *reversals* are possible.
However, looking at the Cash Flow statement "Adjustments For Impairment Loss... 1,140". In the indirect method, you add back non-cash expenses. If it were a reversal (gain), you would subtract it. The fact that it is listed as a positive adjustment in the "Adjustments" list (which sums to CFO) suggests it was **added back**.
Let's verify the sign convention in the provided data.
"Adjustments For Losses Gains On Disposal... -524". A gain is subtracted. So negative means subtract.
"Adjustments For Impairment... 1,140". Positive means add.
Therefore, the 1,140 is treated as an **expense/charge** that is added back.
So, FFO should include +1,140.

Recalculating FFO with +1,140:
$FFO = 13,887 (\text{NI}) + 7,205 (\text{D\&A}) + 1,140 (\text{Impairment}) - 524 (\text{Gain Disp}) - 296 (\text{Equity Diff}) + 18 (\text{SBC})$
$FFO = 21,430$ million EUR.

Net Debt = 21,713 million EUR.

Ratio = $21,430 / 21,713 \approx 0.987$

Let's double check the Equity Income adjustment.
S&P FFO usually does *not* adjust for equity income unless it's a significant portion and non-cash. Eni's equity income is 1,841 vs NI 13,887. It's significant.
The cash dividend is 1,545.
The non-cash part is 296.
If we don't adjust for equity income, FFO = $13,887 + 7,205 + 1,140 - 524 + 18 = 21,726$.
Ratio = $21,726 / 21,713 \approx 1.00$.

S&P methodology for E&P companies:
FFO = Net Income + DD&A + Impairment + Exploration Expense (if expensed) - Gains on Asset Sales.
Eni expenses exploration? "Write Off Of Tangible And Intangible Assets" 599. This might include exploration write-offs. These are non-cash charges included in NI. We should add them back.
Add back Write-offs: 599.
New FFO = $21,726 + 599 = 22,325$.
Ratio = $22,325 / 21,713 \approx 1.03$.

Let's check if "Write Off" is already in D&A or Impairment. Usually separate.
So, FFO ≈ 22,325.

Net Debt Check:
Did we miss any debt?
"Shortterm Borrowings" 4,446
"Current Portion Of Longterm Borrowings" 3,097
"Longterm Borrowings" 19,374
"Current Lease Liabilities" 884
"Noncurrent Lease Liabilities" 4,067
Total = 31,868.
Cash = 10,155.
Net Debt = 21,713.

Ratio = $22,325 / 21,713 = 1.028$.

Rounding to two decimal places: 1.03.

If we use the simpler "NI + D&A" (21,092) and ignore impairments/gains/write-offs:
Ratio = $21,092 / 21,713 = 0.97$.

S&P is specific about adding back impairments and exploration write-offs for E&P.
So 1.03 is more methodologically accurate.

Let's consider the Perpetual Bonds. If they are treated as debt, Net Debt increases.
If Perpetuals are, say, 2-3 billion, Net Debt becomes ~24 billion.
Ratio becomes $22.3 / 24 \approx 0.93$.
However, without the principal amount, we cannot include them. The prompt provides "Decrease Through Coupon Payment... 138". This is the cash flow, not the balance.
We will proceed with the explicit debt instruments.

Final Estimate:
FFO ≈ 22,325 million EUR
Net Debt ≈ 21,713 million EUR
Ratio ≈ 1.03

<answer>1.03</answer>