I'll work through this step-by-step for ENI S.P.A., which is an integrated oil and gas company (primarily E&P, but also downstream and midstream operations).

## Step 1: Identify the Relevant Industry

ENI S.P.A. is a major integrated oil and gas company. Based on the methodologies provided, this falls under **Oil And Gas Exploration And Production (E&P)**. While ENI is integrated, the E&P methodology is most relevant for the core business. The methodology states: "For integrated players, the appropriate measure depends on the degree of vertical and horizontal integration."

Given ENI's structure as a major integrated oil and gas company, I'll apply the E&P methodology with consideration for its integrated nature.

## Step 2: Estimate Adjusted_EBITDA

First, let me reconstruct EBITDA from the income statement data:

From the facts:
- "Profit Loss From Operating Activities" 2022: 17,510,000,000 EUR (this is EBIT/Operating Profit)
- "Depreciation And Amortisation Expense" 2022: 7,205,000,000 EUR

**EBITDA = Operating Profit + Depreciation and Amortization**
EBITDA = 17,510,000,000 + 7,205,000,000 = **24,715,000,000 EUR**

Now for adjustments:

**Lease adjustments:** The E&P methodology mentions lease adjustments. Looking at the data:
- Right-of-use assets: 4,821,000,000 EUR (2022)
- Current lease liabilities: 948,000,000 EUR (2022)
- Noncurrent lease liabilities: 4,389,000,000 EUR (2022)

For S&P purposes, operating leases are typically capitalized. The total lease liabilities = 948,000,000 + 4,389,000,000 = 5,337,000,000 EUR.

However, under IFRS 16, leases are already on balance sheet. For EBITDA, S&P typically adds back lease-related depreciation/amortization to get a "clean" EBITDA. But since IFRS 16 is already applied, the reported EBITDA may already include this. Let me check if we need to adjust.

Actually, for S&P adjusted EBITDA with IFRS 16, they typically:
- Add back lease depreciation (part of D&A) to get pre-IFRS 16 EBITDA equivalent, OR
- Keep as is if using standard approach

Given the complexity, let me use the standard approach where reported EBITDA under IFRS 16 is used, but we adjust debt for leases.

**Nonrecurring items:**
Looking at the data:
- "Impairment Loss Reversal Of Impairment Loss Recognised In Profit Or Loss" 2022: 1,140,000,000 EUR (this is a reversal/gain)
- "Write Off Of Tangible And Intangible Assets" 2022: 599,000,000 EUR (loss)

For S&P, impairment reversals and write-offs are often treated as nonrecurring or normalized. However, in oil and gas, impairments can be cyclical. 

Let me look more carefully:
- "Other Operating Income Expense" 2022: -1,736,000,000 EUR (net expense)
- "Impairment Loss Reversal Of Impairment Loss Recognised In Profit Or Loss" 2022: 1,140,000,000 EUR (positive = reversal/gain)

The impairment reversal of 1,140,000,000 EUR is a gain that S&P would typically subtract as nonrecurring.
The write-off of 599,000,000 EUR is a loss that S&P would typically add back as nonrecurring.

Net nonrecurring adjustment = +599,000,000 - 1,140,000,000 = -541,000,000 EUR (net subtraction)

Actually, let me reconsider. Write-offs are often considered part of normal operations in capital-intensive industries. S&P typically focuses on truly nonrecurring items like restructuring, asset sales, etc.

Looking at "Adjustments For Losses Gains On Disposal Of Noncurrent Assets" in cash flow: 524,000,000 EUR (gain, so negative in adjustments)

For EBITDA, I'll use a more conservative approach:
- Start with reported EBITDA
- Add back nonrecurring losses, subtract nonrecurring gains

From cash flow adjustments, "Other Adjustments To Reconcile Profit Loss" = -2,773,000,000 EUR (negative means added back to profit, so these were expenses)

Let me be more systematic. S&P typically defines Adjusted EBITDA as:
- EBITDA + nonrecurring losses - nonrecurring gains ± other normalizations

For ENI, given the volatile commodity environment and integrated nature, I'll focus on major clearly nonrecurring items. The impairment reversal of 1,140,000,000 EUR seems like a clear candidate to subtract.

**Joint venture adjustments:**
"Share Of Profit Loss Of Equity Accounted Investments" 2022: 1,841,000,000 EUR (profit)

For proportional consolidation, S&P may add proportional EBITDA from JVs. However, this gets complex. The equity-accounted investment value is 5,887,000,000 EUR (2022). Without detailed JV financials, I'll note this but may not fully adjust.

For practical purposes, let me use:
**Adjusted_EBITDA = 24,715,000,000 EUR** (base case, with minimal adjustments for now)

Actually, let me add back the impairment reversal as a gain to subtract, and write-off as loss to add:
Adjusted_EBITDA = 24,715,000,000 + 599,000,000 - 1,140,000,000 = 24,174,000,000 EUR

But wait - the operating profit of 17,510,000,000 already includes these. Let me verify:
Operating profit includes impairments and write-offs. So:
- If impairment reversal (gain) is in operating profit, we subtract it
- If write-off (loss) is in operating profit, we add it back

From the line items, "Impairment Loss Reversal" and "Write Off" are separate line items that sum into operating profit. So:
Adjusted_EBITDA = 24,715,000,000 + 599,000,000 - 1,140,000,000 = **24,174,000,000 EUR**

However, I want to check if these are truly nonrecurring. In oil & gas, asset write-offs and impairments are somewhat cyclical. Let me use a middle ground - I'll make modest adjustments.

Actually, re-reading S&P methodology more carefully: they normalize for nonrecurring items. For an integrated oil company in 2022 with high oil prices, impairments might be reversing prior impairments. Let me be more conservative and use reported EBITDA with minimal adjustment.

Let me use: **Adjusted_EBITDA = 24,715,000,000 EUR** (reported, accepting IFRS 16 basis)

Or, if we want to add back lease depreciation to get "pre-IFRS 16" EBITDA:
We need to estimate lease depreciation. Right-of-use assets are 4,821,000,000. Typical depreciation period for leases might be 5-10 years. Rough estimate: ~600,000,000 per year.

But S&P under IFRS 16 typically uses reported EBITDA and adjusts debt. So I'll stick with:
**Adjusted_EBITDA = 24,715,000,000 EUR**

## Step 3: Estimate FFO

Baseline formula: FFO = Adjusted_EBITDA - cash_interest - cash_taxes

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

Wait - I need to check if interest paid is the right number. Also, we need to consider if dividends from JVs should be added.

From cash flow:
- "Dividends Received Classified As Operating Activities" 2022: 1,545,000,000 EUR
- "Interest Received Classified As Operating Activities" 2022: 116,000,000 EUR

For FFO, S&P typically:
- Starts with Adjusted EBITDA
- Subtracts cash interest paid (net of interest received, or gross)
- Subtracts cash taxes paid
- Adds dividends received from investments (sometimes)

Standard FFO = Adjusted EBITDA - cash interest paid - cash taxes paid

But we need to be careful about what's in operating cash flow. Let me use:
- Cash interest paid: 851,000,000 EUR
- Cash taxes paid: 8,488,000,000 EUR

However, looking at "Finance Costs" in P&L: 9,333,000,000 EUR, and "Finance Income": 8,450,000,000 EUR. The net finance cost is 883,000,000 EUR.

Cash interest paid of 851,000,000 seems low relative to P&L finance costs. This might be because some interest is capitalized or the P&L includes non-cash items.

For S&P FFO, we typically use:
FFO = Adjusted EBITDA - cash interest - cash taxes

But we also need to consider working capital and other items. Actually, let me re-read the S&P definition.

S&P FFO is typically defined as:
FFO = Funds from operations = Net income + depreciation + amortization + other non-cash items - working capital changes... 

Actually, more standard S&P definition:
FFO = Adjusted EBITDA - cash interest - cash taxes

Or alternatively from cash flow statement:
FFO = Cash flow from operations + after-tax interest expense - working capital changes

Let me use the direct approach:
FFO = Adjusted_EBITDA - cash_interest - cash_taxes

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

But wait - this seems high. Let me verify with another approach.

From cash flow statement:
"Cash Flows From Used In Operating Activities" 2022: 17,460,000,000 EUR

This includes working capital changes, interest, taxes, etc. 

To get FFO from operating cash flow:
FFO = Operating Cash Flow + cash interest paid + cash taxes paid - working capital changes - other non-FFO items

Actually, standard S&P approach:
FFO = Net income + D&A + deferred taxes + other non-cash charges - after-tax gains on asset sales + other adjustments

Let me try:
Net income (Profit Loss) 2022: 13,961,000,000 EUR
+ D&A: 7,205,000,000 EUR
+ Impairment reversal: -1,140,000,000 EUR (this is a gain, so subtract)
+ Write-off: 599,000,000 EUR
+ Other non-cash in operating profit: need to identify

From "Other Operating Income Expense": -1,736,000,000 EUR (expense)

Let me check cash flow adjustments:
"Adjustments For Depreciation And Amortisation Expense": 7,205,000,000
"Adjustments For Impairment Loss Reversal": 1,140,000,000 (positive means it was subtracted from profit, so this is a gain/reversal)
"Write Off Of Tangible Or Intangible Assets": 599,000,000
"Adjustments For Undistributed Profits Of Investments": 1,841,000,000 (this is equity earnings, added back)
"Adjustments For Losses Gains On Disposal Of Noncurrent Assets": -524,000,000 (gain, so negative adjustment)
"Adjustments For Dividend Income": -351,000,000 (subtract dividend income)
"Adjustments For Interest Income": -159,000,000
"Adjustments For Interest Expense": 1,033,000,000
"Adjustments For Income Tax Expense": 8,088,000,000
"Other Adjustments To Reconcile Profit Loss": -2,773,000,000

Sum of adjustments: 7,205 + 1,140 + 599 + 1,841 - 524 - 351 - 159 + 1,033 + 8,088 - 2,773 = 16,199,000,000

Net income 13,961 + adjustments 16,199 = 30,160,000,000 (should equal operating cash flow before working capital)

Then working capital and other items:
"Increase Decrease In Working Capital": 1,279,000,000
"Adjustments For Decrease Increase In Inventories": -2,528,000,000
"Adjustments For Decrease Increase In Trade Account Receivable": -1,036,000,000
"Adjustments For Increase Decrease In Trade Account Payable": 2,284,000,000
"Adjustments For Provisions": 2,028,000,000
"Adjustments For Increase Decrease In Other Assets And Liabilities": -2,027,000,000
"Adjustments For Increase Decrease In Employee Benefit Liabilities": 39,000,000
"Dividends Received": 1,545,000,000
"Interest Received": 116,000,000
"Interest Paid": -851,000,000
"Income Taxes Paid Refund": -8,488,000,000

Let me verify: 30,160 + 1,279 - 2,528 - 1,036 + 2,284 + 2,028 - 2,027 + 39 + 1,545 + 116 - 851 - 8,488 = 22,521... not matching 17,460.

Hmm, let me recheck. The "Increase Decrease In Working Capital" of 1,279 might be the net of some items.

Actually, looking more carefully at the structure, I think "Increase Decrease In Working Capital" is the total, and the other items are components. Let me check: -2,528 - 1,036 + 2,284 + 2,028 - 2,027 + 39 = -1,240, which doesn't equal 1,279.

This is getting complex. Let me use a simpler approach and focus on the key S&P formula.

For S&P purposes, FFO is typically calculated as:
**FFO = Net income + Depreciation & Amortization + Deferred income taxes + Other non-cash items - Gain on sale + Interest expense - Interest income**

Or more practically for this case, using the cash flow approach:
FFO = Cash from operations + cash interest paid + cash taxes paid - working capital changes

From cash flow: Operating cash flow = 17,460,000,000
This includes: -851 interest paid, -8,488 taxes paid, +1,279 working capital, +1,545 dividends, +116 interest received

To get FFO (before working capital):
FFO = 17,460 - 1,279 (remove working capital) + 851 (add back interest) + 8,488 (add back taxes) - 1,545 (remove dividends? or keep?) - 116 (remove interest received? or keep?)

Actually, S&P FFO typically excludes working capital changes and includes interest and taxes as deductions. So:

FFO = Operating CF - Working capital changes + Interest paid + Taxes paid - Dividends received (sometimes)

= 17,460 - 1,279 + 851 + 8,488 - 1,545 = 23,975? No that doesn't work either.

Let me use the most standard S&P approach:
**FFO = Adjusted EBITDA - Cash Interest - Cash Taxes**

With Adjusted EBITDA = 24,715,000,000
Cash interest paid = 851,000,000
Cash taxes paid = 8,488,000,000

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

But I need to check if this includes dividends from JVs. S&P sometimes includes dividends received in FFO for equity-accounted investments. The E&P methodology mentions "Adjustments For Undistributed Profits Of Investments" which suggests we should consider this.

Actually, looking at the E&P methodology section on FFO: it mentions FOCF (funds from operations after capex) and DCF (discretionary cash flow). Let me re-read...

The methodology says: "Our preferred supplementary ratios in the sector are FOCF to debt and DCF to debt." But for core ratios, FFO to debt is used.

For FFO specifically, let me use a more comprehensive definition that includes dividends:

FFO = Net income + D&A + deferred taxes + other non-cash - gains on sales + dividends from investments (if not in earnings)

Actually, from the equity method: "Share Of Profit Loss Of Equity Accounted Investments" is 1,841,000,000 included in profit, but "Dividends Received" is 1,545,000,000. The undistributed portion is 1,841,000,000 - 1,545,000,000 = 296,000,000 (approx, though these may not be directly comparable).

For S&P, when using equity method earnings, they may add back the undistributed portion or use dividends. The cash flow shows "Adjustments For Undistributed Profits Of Investments" of 1,841,000,000, which means they add back equity earnings (subtracting them from profit to get cash basis).

Let me try yet another approach - using the cash flow reconciliation to build FFO:

Start with Net income: 13,961,000,000
Add back D&A: 7,205,000,000
Add back other non-cash in adjustments: 
- Impairment reversal: -1,140,000,000 (gain, so negative addback)
- Write-off: 599,000,000
- Undistributed profits of investments: 1,841,000,000 (this removes equity earnings)
- Gains on disposal: -524,000,000
- Dividend income: -351,000,000
- Interest income: -159,000,000
- Interest expense: 1,033,000,000
- Income tax expense: 8,088,000,000
- Other adjustments: -2,773,000,000

This gets messy. Let me use the cleanest approach:

**FFO = Cash Flow from Operating Activities + Cash Interest Paid + Cash Taxes Paid - Working Capital Changes - Dividends Received from Investments**

= 17,460,000,000 + 851,000,000 + 8,488,000,000 - 1,279,000,000 - 1,545,000,000
= 23,975,000,000? 

No wait, that's double counting. Operating CF already includes interest paid, taxes paid, working capital, and dividends received.

Let me think again. Operating CF = EBIT + D&A - ΔWC - Cash taxes - Cash interest + Dividends received + Interest received...

Actually, standard: Operating CF = Net income + D&A + other non-cash - ΔWC

And: Net income = EBIT - Interest expense - Taxes

So: Operating CF = EBIT - Interest expense - Taxes + D&A + other non-cash - ΔWC

For FFO, S&P wants: EBIT + D&A - Cash interest - Cash taxes = EBITDA - Cash interest - Cash taxes (approximately)

But this excludes working capital. S&P FFO is meant to be a "normalized" cash flow before working capital.

Actually, I think the confusion is between "FFO" and "Operating CF". S&P FFO is typically:
FFO = Net income from continuing operations + D&A + deferred taxes + other non-cash charges - gain on sale + after-tax interest expense

Or: FFO = EBITDA - Cash interest - Cash taxes (this is a common simplification)

Given the complexity, let me use: **FFO = 15,376,000,000 EUR** (from EBITDA - cash interest - cash taxes)

But I want to also consider if we should add back dividends from equity investments. In the E&P sector, these are often included. Let me check: dividends received of 1,545,000,000 are in operating CF. If we use EBITDA approach, we're not including them. 

Alternatively, using: FFO = Operating CF + Interest paid + Taxes paid - WC changes - Dividends received
= 17,460 + 851 + 8,488 - 1,279 - 1,545 = 23,975? No, operating CF already includes these.

Let me try: FFO = Operating CF - WC changes (since WC is volatile)
= 17,460 - 1,279 = 16,181, then adjust?

Actually, the most common S&P formula for FFO from operating CF is:
FFO = Operating CF + Cash interest paid + Cash taxes paid - Working capital changes

Because operating CF = (EBITDA - cash interest - cash taxes) + WC changes - other items

So: FFO = EBITDA - cash interest - cash taxes = Operating CF - WC changes + cash interest + cash taxes - cash interest - cash taxes... 

Let me just verify with numbers:
Operating CF = 17,460
Components: EBIT(17,510) + D&A(7,205) - non-cash items in EBIT + WC changes + other = 17,460

Actually from cash flow statement, the reconciliation shows:
Profit before tax: 22,049
+ D&A: 7,205
+ Impairment reversal: 1,140
+ Write-off: 599
+ Undistributed profits: 1,841
- Gains on disposal: -524
- Dividend income: -351
- Interest income: -159
+ Interest expense: 1,033
+ Income tax expense: 8,088
+ Other adjustments: -2,773
= 38,148 (this is before working capital and other items)

Then +WC 1,279 + other items + dividends 1,545 + interest received 116 - interest paid 851 - taxes paid 8,488 = 17,460

So pre-WC, pre-dividends, pre-interest, pre-taxes = 38,148
Then -8,488 taxes -851 interest +1,279 WC +1,545 dividends +116 interest received = 17,460

For FFO, S&P typically uses: pre-WC operating CF - cash interest - cash taxes + dividends
= 38,148 - 851 - 8,488 + 1,545? No...

Let me use the simplest consistent approach:
**FFO = EBITDA - Cash Interest - Cash Taxes = 24,715 - 851 - 8,488 = 15,376 million EUR**

But wait, I need to check if EBITDA includes dividends from equity investments. It doesn't - equity earnings are below operating profit. So:

EBIT = 17,510 includes: operating activities, excludes equity earnings
Equity earnings = 1,841 are in "Investment Income Expense" below EBIT

So EBIT = 17,510, EBITDA = 24,715, and we need to consider if FFO should include equity earnings or dividends.

For S&P, FFO typically includes the cash dividends received from equity investments, not the equity earnings. So:

Adjusted approach: FFO = (EBITDA excluding equity earnings) - cash interest - cash taxes + dividends received
= 24,715 - 851 - 8,488 + 1,545 = **16,921,000,000 EUR**

Or if we start from a broader base: 

Actually, let me check - is EBIT of 17,510 before or after equity earnings? Looking at the structure:
"Profit Loss From Operating Activities" = 17,510
Then "Finance Income" = 8,450
"Finance Costs" = 9,333
"Finance Income Cost" = -925 (net)
Then "Share Of Profit Loss Of Equity Accounted Investments" = 1,841
Then "Other Income Expense From Investments" = 3,623
"Investment Income Expense" = 5,464
Then "Profit Loss Before Tax" = 22,049

So: 17,510 (operating) - 925 (net finance) + 1,841 (equity earnings) + 3,623 (other investment) = 22,049? 
17,510 - 925 = 16,585; 16,585 + 1,841 + 3,623 = 22,049. Yes!

So operating profit of 17,510 is BEFORE equity earnings and investment income. 

For FFO, S&P might want to include the cash from these investments. The E&P methodology mentions "FOCF" which assumes maintenance capex. For FFO, let me use:

**FFO = 15,376,000,000 EUR** (base EBITDA approach)

Or with dividends: **16,921,000,000 EUR**

Given the E&P methodology emphasis on cash generation and the importance of JV dividends, let me use:
**FFO = 16,921,000,000 EUR** (including dividends received)

Actually, rethinking: S&P typically defines FFO as:
FFO = Funds from operations = Net income + D&A + deferred taxes + other non-cash - gains on sales + after-tax interest expense

Or from EBITDA: FFO = EBITDA - cash interest - cash taxes

This is the standard definition. Dividends from equity investments are typically NOT added back to FFO because they're already in net income if using equity method, or they're separate if using cost method.

But wait - if we use EBITDA - cash interest - cash taxes, we're starting from a pre-equity earnings, pre-dividends base. The equity earnings and dividends are below the line.

For a comprehensive FFO, S&P sometimes uses:
FFO = Net income + D&A + non-cash items - gains + interest expense (after tax)

Let me calculate:
Net income = 13,961
+ D&A = 7,205
+ Impairment reversal (gain, so subtract) = -1,140
+ Write-off = 599
+ Undistributed profits of investments (remove equity earnings) = 1,841
- Gains on disposal = -524
- Dividend income (already in net income, but was it?) = -351... 

This is getting circular. Let me use the cleanest approach:

**FFO = Operating Cash Flow + Cash Interest Paid + Cash Taxes Paid - Working Capital Changes**

= 17,460 + 851 + 8,488 - 1,279 = **25,520,000,000 EUR**

Then subtract dividends received (since they're investment income, not operating):
= 25,520 - 1,545 = **23,975,000,000 EUR**

Hmm, but this seems high. Let me verify: 25,520 - 1,545 = 23,975? No wait, I said 25,520 - 1,545 but that's not what I calculated.

Actually: 17,460 + 851 + 8,488 - 1,279 = 25,520. Then if we remove dividends received (which are in operating CF): 25,520 - 1,545 = 23,975.

But should we remove dividends? In E&P, dividends from equity investments are often considered part of operating cash flow for FFO purposes, especially if they're from core JVs.

Let me check S&P guidance more carefully. For E&P companies, S&P typically includes dividends from equity investments in FFO if they're recurring and from core operations.

Given ENI's integrated nature and the fact that equity investments are core to operations (many oil companies have JVs for major projects), I'll include dividends.

**FFO = 25,520,000,000 EUR** (approximately)

Wait, let me recheck: 17,460 + 851 + 8,488 - 1,279 = 25,520. But this includes interest received of 116 and excludes... 

Actually, let me be more careful. Operating CF includes:
+ Dividends received: 1,545
+ Interest received: 116
- Interest paid: 851
- Taxes paid: 8,488
+ WC changes: 1,279 (positive means source of cash, so added)

So: FFO = Operating CF - WC changes + Interest paid + Taxes paid - Interest received - Dividends received? 

No, the standard is:
FFO = Operating CF + Interest paid + Taxes paid - WC changes

This gives: 17,460 + 851 + 8,488 - 1,279 = 25,520

But this "FFO" includes dividends and interest received. Is that correct?

Actually, I think I'm confusing myself. Let me look at this differently.

Standard S&P FFO calculation from cash flow statement:
1. Start with Cash from Operations
2. Add back: decrease in working capital (or subtract increase)
3. Add back: cash taxes paid
4. Add back: cash interest paid
5. Subtract: dividends received (if classified as operating - move to investing)
6. Subtract: interest received (if classified as operating - move to investing)

Or: FFO = Cash from Operations - Working Capital Changes + Cash Interest Paid + Cash Taxes Paid

This assumes Cash from Operations already includes interest paid, taxes paid, and working capital changes.

So: 17,460 - 1,279 + 851 + 8,488 = 25,520

But wait, if operating CF already includes -851 interest paid and -8,488 taxes paid and +1,279 WC changes, then:
Operating CF = "Core FFO" - 851 - 8,488 + 1,279 + other items
"Core FFO" = Operating CF + 851 + 8,488 - 1,279 - other items

The "other items" include dividends received (1,545) and interest received (116).

So: Core FFO = 17,460 + 851 + 8,488 - 1,279 - 1,545 - 116 = 23,859

Or if we include dividends and interest as part of FFO:
FFO = 17,460 + 851 + 8,488 - 1,279 = 25,520

I think the key question is whether dividends and interest received are part of "operating" FFO for an oil company. For E&P companies, dividends from equity-accounted JVs are often considered part of core FFO.

Let me use a middle ground: include dividends (as they're core to E&P operations), exclude interest received (as that's financial):

**FFO = 25,520 - 116 = 25,404,000,000 EUR** (excluding interest received)

Or approximately **25,000,000,000 EUR** rounded.

Actually, let me step back and use a simpler, more defensible approach. The E&P methodology says FFO is used, and for integrated companies, they look at historical ratios. Let me use the standard definition that S&P typically applies:

**FFO = Net income + Depreciation & Amortization + Deferred income taxes + Other non-cash charges - Gain on sale of assets + After-tax interest expense**

From the data:
Net income = 13,961
+ D&A = 7,205
+ Deferred taxes: need to estimate. "Net Deferred Tax Assets" changed from 2,713 to 4,569, so increase of 1,856. But this is balance sheet. From cash flow, "Adjustments For Income Tax Expense" = 8,088 (this is adding back tax expense, not deferred specifically).
+ Other non-cash: impairment reversal (-1,140, gain so subtract), write-off (599), undistributed profits (1,841 - but this is equity earnings removal)
- Gain on sale: -524
+ After-tax interest expense: interest expense was 1,033 in adjustments, or 9,333 in P&L. Let's use 9,333 * (1 - tax rate). Tax rate = 8,088/22,049 = 36.7%. So after-tax interest = 9,333 * 0.633 = 5,908? No wait, we add back interest expense pre-tax in standard FFO.

Actually, standard FFO adds back interest expense (not after-tax) because FFO is pre-financing. So:
+ Interest expense = 9,333 (from P&L)

But then we need to subtract cash interest, not add back interest expense. I'm confusing different FFO definitions.

Let me use the most common S&P corporate FFO definition:
**FFO = Cash from Operations + Cash Interest Paid + Cash Taxes Paid - Working Capital Changes**

= 17,460 + 851 + 8,488 - 1,279 = **25,520,000,000 EUR**

This is approximately **25.5 billion EUR**.

Given the uncertainty, let me also check if this aligns with EBITDA - cash interest - cash taxes:
EBITDA = 24,715
- Cash interest = 851
- Cash taxes = 8,488
= 15,376

These are very different! The difference is mainly working capital (1,279), dividends (1,545), interest received (116), and other non-cash items.

The EBITDA approach gives "FFO before working capital" while the cash flow approach gives "FFO including working capital benefits." 

For S&P, FFO is typically AFTER working capital normalization. So we should exclude working capital. But we should include dividends if they're recurring.

Let me use: **FFO = 24,000,000,000 EUR** as a rough midpoint, or more precisely:

From the reconciliation: "Core operating cash generation" before WC and financing items = 38,148 (from profit reconciliation) + some items.

Actually, let me use the EBITDA-based FFO as it's more standard for leverage ratios:
**FFO = 15,376,000,000 EUR**

But this seems low for a company with 13.9 billion net income and 7.2 billion D&A.

Let me verify: Net income 13,961 + D&A 7,205 = 21,166. Then - cash interest 851 - cash taxes 8,488 = 11,827? No, that's not right either.

Actually: FFO = Net income + D&A + non-cash charges - gains + interest expense (added back because FFO is pre-interest) - interest income... 

This is: 13,961 + 7,205 + (-1,140 + 599 + 1,841 - 524 - 351 - 159 + 1,033 + 8,088 - 2,773) + 9,333 - 8,450... 

Too messy. Let me use the cash flow approach as it's more direct:

**FFO = 25,520,000,000 EUR** (from Cash from Operations + Interest paid + Taxes paid - WC changes)

I'll round to **25,500,000,000 EUR** or use 25,520 precisely.

Actually, I want to double-check this makes sense. Operating CF is 17,460. This includes:
- WC benefit: +1,279
- Interest paid: -851
- Taxes paid: -8,488
- Dividends received: +1,545
- Interest received: +116

So "operating" before these = 17,460 - 1,279 + 851 + 8,488 - 1,545 - 116 = 23,859? No wait, I'm reversing signs inconsistently.

Let me be very careful:
Operating CF = 17,460
This INCLUDES: +1,279 (WC source), -851 (interest use), -8,488 (tax use), +1,545 (dividends source), +116 (interest source)

To get "FFO" which excludes WC but includes operating dividends and excludes financing interest:
FFO = Operating CF - WC_changes - Interest_received + Interest_paid - Dividends_received? 

No, standard S&P FFO includes dividends from investments (if operating) and uses cash interest/taxes.

Let me use: FFO = EBITDA + Dividends received - Cash interest - Cash taxes
= 24,715 + 1,545 - 851 - 8,488 = **16,921,000,000 EUR**

This seems more reasonable and consistent with the EBITDA approach.

Or: FFO = Operating CF + Cash interest + Cash taxes - WC changes - Interest received
= 17,460 + 851 + 8,488 - 1,279 - 116 = 25,404

The difference between 16,921 and 25,404 is 7,483, which is roughly the other adjustments (non-cash items, gains/losses, etc.).

For S&P FFO, the standard is to normalize these. The cash flow approach (25,404) includes all non-cash adjustments that are in operating CF. The EBITDA approach (16,921) starts cleaner.

I think the most standard S&P FFO for this purpose is:
**FFO = 16,921,000,000 EUR** (EBITDA + dividends - cash interest - cash taxes)

But let me also consider: should we include interest received? For operating companies, S&P sometimes includes it in FFO if it's from operating cash balances. But typically, FFO = EBITDA - cash interest - cash taxes, where "cash interest" is net interest paid (interest paid - interest received).

Net cash interest = 851 - 116 = 735
Then FFO = 24,715 + 1,545 - 735 - 8,488 = **17,037,000,000 EUR**

Or approximately **17,000,000,000 EUR**.

Given all this analysis, let me settle on:
**FFO = 17,000,000,000 EUR** (rounded) or more precisely about 16,900,000,000 EUR.

Actually, let me use a slightly different approach that S&P often uses for oil companies:
FFO = Cash Flow from Operating Activities - Working Capital Changes

= 17,460 - 1,279 = **16,181,000,000 EUR**

This is "FFO" in the sense of sustainable cash generation before working capital.

Then add back net interest (interest paid - interest received) and taxes? No, those are already in operating CF.

Hmm, Operating CF already includes -851 interest, -8,488 taxes, +1,545 dividends, +116 interest received, +1,279 WC.

So: Operating CF - WC changes = 17,460 - 1,279 = 16,181. This includes -851 - 8,488 + 1,545 + 116 = -7,678 net financing/investment items.

For "FFO" we want pre-financing, so add back net interest paid and taxes:
16,181 + 851 - 116 + 8,488 = 25,404? No, that's going back to pre-tax, pre-interest.

I think the cleanest is:
FFO = (Operating CF - WC changes) + Net interest paid + Taxes paid
= 16,181 + (851 - 116) + 8,488 = 25,404

But this double counts if operating CF already includes these.

Let me try: FFO = EBIT + D&A - Cash taxes
= 17,510 + 7,205 - 8,488 = 16,227

Or with dividends: 16,227 + 1,545 = 17,772

Or: FFO = Net income + D&A + Interest expense - Interest income + Cash taxes - Taxes accrued... 

This is too complex. Let me use the standard formula that S&P publishes:
**FFO = Funds from operations = Net income + depreciation and amortization + deferred income taxes + other non-cash items**

From cash flow, the "other non-cash items" that adjust profit to pre-WC cash flow:
= 1,140 + 599 + 1,841 - 524 - 351 - 159 + 1,033 + 8,088 - 2,773 = 8,994

So: FFO = 13,961 + 7,205 + 8,994 = 30,160? No, this is the pre-WC operating cash flow, not FFO.

Actually, looking at this, 30,160 matches my earlier calculation of "profit before tax reconciliation" sum. And 30,160 - 8,488 taxes - 851 interest + 1,279 WC + 1,545 dividends + 116 interest received = 23,761, not 17,460. 

Wait, let me recheck: 30,160 + 1,279 - 851 - 8,488 + 1,545 + 116 = 23,761. But operating CF is 17,460. Difference is 6,301. 

I must have misidentified some items. Let me recheck the reconciliation sum:
7,205 + 1,140 + 599 + 1,841 - 524 - 351 - 159 + 1,033 + 8,088 - 2,773 
= 7,205 + 1,140 = 8,345
+ 599 = 8,944
+ 1,841 = 10,785
- 524 = 10,261
- 351 = 9,910
- 159 = 9,751
+ 1,033 = 10,784
+ 8,088 = 18,872
- 2,773 = 16,099

So adjustments = 16,099, not 16,199 or whatever I had.

Then: 13,961 + 16,099 = 30,060 (pre-WC, pre-tax/interest/dividends operating)

Then +1,279 WC - 851 interest + 116 interest received + 1,545 dividends - 8,488 taxes = 30,060 + 1,279 - 851 + 116 + 1,545 - 8,488 = 23,661

Still not 17,460. There's a 6,201 difference. I must be missing something in the reconciliation.

Actually, looking back at the original data, I see "Other Adjustments To Reconcile Profit Loss" = -2,773,000,000. This might include working capital or other items. 

Also, I notice "Adjustments For Income Tax Expense" = 8,088, but this is the tax expense, not necessarily all cash or non-cash.

Given the complexity and potential for error in manual reconciliation, let me use the most direct S&P FFO formula:

**FFO = EBITDA - Cash Interest - Cash Taxes + Dividends from equity investments**

= 24,715,000,000 - 851,000,000 - 8,488,000,000 + 1,545,000,000
= **16,921,000,000 EUR**

I'll use **FFO = 16,921,000,000 EUR** or rounded to **16,900,000,000 EUR**.

## Step 4: Estimate Adjusted_Debt

Baseline formula: Adjusted_Debt = (reported_debt + leases + pension_deficit + guarantees + hybrid_debt_portion + other_debt_like_items) - eligible_cash

From balance sheet:
**Short-term borrowings:**
- 2022: 2,299,000,000 EUR
- Related parties: 233,000,000 EUR
Total short-term borrowings = 2,532,000,000 EUR

**Current portion of long-term borrowings:**
- 2022: 1,781,000,000 EUR
- Related parties: 21,000,000 EUR
Total current portion = 1,802,000,000 EUR

**Long-term borrowings:**
- 2022: 23,714,000,000 EUR
- Related parties: 5,000,000 EUR
Total long-term borrowings = 23,719,000,000 EUR

**Total reported debt** = 2,532 + 1,802 + 23,719 = **28,053,000,000 EUR**

**Lease liabilities:**
- Current lease liabilities: 948,000,000 EUR
- Noncurrent lease liabilities: 4,389,000,000 EUR
- Related parties: 17,000,000 + 1,000,000 = 18,000,000 EUR
Total lease liabilities = 5,355,000,000 EUR

Under IFRS 16, these are already in debt. For S&P adjusted debt, they typically include lease liabilities as debt-like obligations. Since they're already in reported borrowings? No, lease liabilities are separate from borrowings in the balance sheet.

So we add lease liabilities: + 5,355,000,000 EUR

**Pension deficit:**
"Noncurrent Provisions For Employee Benefits" = 819,000,000 EUR (2022)

This is a pension/employee benefit obligation. S&P typically treats unfunded pension deficits as debt-like. The provision is 819,000,000 EUR. We need to check if this is net of plan assets. Given it's a "provision" on balance sheet, it's likely the net liability. 

Add: + 819,000,000 EUR

**Guarantees:** Not explicitly stated in the data. Assume 0 or minimal.

**Hybrid debt portion:** Looking for perpetual or hybrid instruments. I see "Proceeds From Issuing Other Equity Instruments" and "Payments Of Other Equity Instruments" in cash flow, suggesting hybrid equity/debt instruments. Also "Decrease Through Coupon Payment On Perpetual Subordinated Bonds Equity" = 61,000,000 EUR in 2021-2022 and 138,000,000 EUR in 2022-2023. And "Increase Decrease Through Net Issue Reimbursement Of Perpetual Subordinated Bonds Equity" = 2,000,000,000 EUR in 2021-2022.

These perpetual subordinated bonds are treated as equity by ENI but may be treated as hybrid debt by S&P. The balance sheet shows "Other Reserves" includes these. 

From equity section: "Other Reserves" 2022 = 6,289,000,000; 2021 = 4,688,000,000. Change includes 2,000,000,000 from perpetual bonds.

S&P typically treats 50% of hybrid equity as debt if it's debt-like. For perpetual subordinated bonds, they might count 50% as debt.

Let me estimate: roughly 2,000,000,000 - 3,000,000,000 of perpetual bonds outstanding. At 50%: + 1,000,000,000 to 1,500,000,000 EUR.

From the cash flow, "Increase Decrease Through Net Issue Reimbursement Of Perpetual Subordinated Bonds Equity" was 2,000,000,000 in 2021-2022 and there were payments of other equity instruments. 

Looking at 2023: "Payments Of Other Equity Instruments" = 138,000,000. And "Other Reserves" increased from 6,289 to 8,785 (increase of 2,496), with various components.

This is complex. Let me assume hybrid debt portion = **1,000,000,000 EUR** (conservative estimate for 50% of perpetual hybrids).

**Other debt-like items:**
- "Other Noncurrent Liabilities" = 2,246,000,000 EUR (includes 415 related parties)
- "Other Current Liabilities" = 15,756,000,000 EUR (includes 339 related parties)

These may include some debt-like obligations. But they're likely operating liabilities.

- "Trade And Other Current Payables" = 21,720,000,000 EUR (includes 2,298 related parties)

For S&P, they sometimes reclassify certain payables or derivative liabilities. But without more detail, I'll focus on the main items.

**Total debt-like items before cash:**
= 28,053 (reported debt) + 5,355 (leases) + 819 (pensions) + 1,000 (hybrid) = **35,227,000,000 EUR**

**Eligible cash:**
"Cash And Cash Equivalents" 2022 = 8,254,000,000 EUR
+ Related parties cash = 2,000,000 EUR
= 8,256,000,000 EUR

Also "Current Financial Assets At Fair Value Through Profit Or Loss" = 6,301,000,000 EUR - these may be liquid investments.

And "Other Current Financial Assets" = 4,308,000,000 EUR (includes 53 related parties)

S&P typically deducts "surplus cash" but not all financial assets. Standard approach:
- Deduct cash and cash equivalents: 8,256,000,000
- May deduct liquid financial assets if truly surplus

For conservative approach, just deduct cash: **8,256,000,000 EUR**

**Adjusted_Debt** = 35,227 - 8,256 = **26,971,000,000 EUR**

Or if we include more liquid assets as cash-like:
+ Current Financial Assets FVTPL: 6,301,000,000
+ Other Current Financial Assets: 4,308,000,000
= Total liquid = 18,865,000,000

But this seems too high - these are likely operating assets (commodity derivatives, receivables, etc.).

For S&P, they typically only deduct "cash and cash equivalents" and sometimes "short-term liquid investments" if clearly surplus.

Let me use: **Adjusted_Debt = 26,971,000,000 EUR** or approximately **27,000,000,000 EUR**

Actually, I want to reconsider the lease treatment. Under IFRS 16, lease liabilities are already included in "debt" if the company has borrowings that include lease obligations. But looking at the balance sheet, "Current Lease Liabilities" and "Noncurrent Lease Liabilities" are separate line items from "Short-term Borrowings" and "Long-term Borrowings". So they're NOT included in reported debt.

However, the right-of-use assets are 4,821,000,000 and lease liabilities are 5,337,000,000 (948 + 4,389). The difference might be due to timing or presentation.

So yes, we add lease liabilities to debt.

Let me also recheck total debt:
Short-term borrowings: 2,299 + 233 = 2,532
Current portion long-term: 1,781 + 21 = 1,802
Long-term borrowings: 23,714 + 5 = 23,719
Total = 28,053

Plus leases: 948 + 4,389 + 17 + 1 = 5,355
Plus pensions: 819
Plus hybrid: 1,000
Less cash: 8,256

Adjusted Debt = 28,053 + 5,355 + 819 + 1,000 - 8,256 = **26,971,000,000 EUR**

## Step 5: Calculate FFO / Adjusted_Debt

Using:
FFO = 16,921,000,000 EUR
Adjusted_Debt = 26,971,000,000 EUR

Ratio = 16,921 / 26,971 = **0.6274**

Or if we use slightly different FFO:
- If FFO = 17,037 (with net interest): 17,037 / 26,971 = 0.6317
- If FFO = 25,520 (cash flow approach): 25,520 / 26,971 = 0.9462

The cash flow approach seems too high for a leverage ratio. The EBITDA-based FFO of ~17 billion seems more appropriate.

Let me also consider if we should use higher FFO. Looking at S&P's typical FFO calculation for oil companies, they often include working capital normalization but also add back certain items.

Actually, let me recalculate FFO more carefully using the standard S&P approach for E&P:

From S&P methodology: "FFO to debt is the preferred measure" for transportation infrastructure, but for E&P they prefer "FOCF to debt and DCF to debt" as supplementary, with FFO still used as core.

For FFO, let me use: 
FFO = Cash from Operations + Cash Interest Paid + Cash Taxes Paid - Working Capital Changes
= 17,460 + 851 + 8,488 - 1,279 = 25,520

But this includes dividends and interest received. For "clean" FFO:
= 25,520 - 1,545 - 116 = 23,859

Or if we keep dividends (core to operations):
= 25,520 - 116 = 25,404

Hmm, 25.4 billion / 27.0 billion = 0.94, which seems high for an oil company leverage ratio.

Let me check with EBITDA approach:
EBITDA = 24,715
- Cash interest = 851
- Cash taxes = 8,488
= 15,376 base
+ Dividends = 1,545
= 16,921

This gives 0.63, which seems more reasonable for an integrated oil company in 2022 with high oil prices.

Actually, I realize I should check if S&P includes dividends in FFO for equity-accounted investments. Looking at typical S&P adjustments, when companies use equity method, S&P sometimes replaces equity earnings with dividends received in FFO. 

Equity earnings = 1,841
Dividends received = 1,545

So if we replace equity earnings with dividends in net income:
Adjusted net income = 13,961 - 1,841 + 1,545 = 13,665
+ D&A = 7,205
+ Other non-cash adjustments (normalize) = roughly 0
= FFO ≈ 20,870

Then - cash interest - cash taxes? No, this is already after interest and taxes.

Actually: FFO = Net income + D&A + interest expense + other non-cash - cash adjustments...

Let me try: 13,961 + 7,205 + 1,033 (interest expense from adjustments) = 22,199
Or with equity earnings replaced: 13,665 + 7,205 + 1,033 = 21,903

This is getting too convoluted. Let me settle on a reasonable estimate.

Given ENI's 2022 performance with high oil prices, strong cash generation, and integrated operations, an FFO/debt ratio around 0.60-0.75 seems reasonable.

Let me use my most defensible calculation:
**FFO = 16,921,000,000 EUR** (EBITDA + dividends - cash interest - cash taxes)
**Adjusted_Debt = 26,971,000,000 EUR**

**FFO / Adjusted_Debt = 16,921 / 26,971 = 0.6274**

But I want to also try a slightly higher FFO that includes more cash generation. If we use operating CF minus working capital changes:
= 17,460 - 1,279 = 16,181
+ Interest paid (since FFO is pre-interest) = 851
+ Taxes paid (since FFO is pre-tax? No, FFO is after tax)
= 16,181 + 851 = 17,032
Or with dividends: 17,032 + 1,545 = 18,577? No, dividends are already in operating CF.

Actually, operating CF of 17,460 already includes +1,545 dividends. So:
Operating CF - WC changes = 16,181 includes dividends.

For FFO, if we want pre-interest: 16,181 + 851 = 17,032
Or pre-interest with dividends kept: 17,032 (already includes dividends)

Then FFO / Debt = 17,032 / 26,971 = 0.6315

Very similar to my 0.6274.

Let me also consider if Adjusted Debt should be higher. If we include more hybrid debt or other liabilities:

Other noncurrent liabilities: 2,246
Other current liabilities: 15,756
Trade payables: 21,720

These are operating liabilities, not debt.

If we include 50% of hybrid as debt: already done at 1,000.

What about deferred tax liabilities? "Net Deferred Tax Liabilities" = 4,835,000,000. S&P sometimes treats deferred taxes as equity or adjusts them. Typically not included in debt.

What about "Other Longterm Provisions" = 13,593,000,000? These could be decommissioning, environmental, etc. S&P sometimes treats these as debt-like if they're related to asset retirement obligations.

For oil companies, ARO (asset retirement obligations) are often significant. "Other Longterm Provisions" of 13,593 might include these. S&P typically adds ARO to debt if they're not already included.

However, these are likely already reflected in the balance sheet as provisions and may be included in operating liabilities. Without clear guidance, I'll keep them out of adjusted debt but note they could increase it.

If we added 50% of other long-term provisions: +6,796
Adjusted Debt = 33,767
FFO/Debt = 16,921 / 33,767 = 0.501

This is lower but still reasonable.

Given S&P's typical approach for E&P companies, let me use a middle ground. They often include ARO-related provisions in debt. Let me add a portion:

"Other Longterm Provisions" = 13,593,000,000. If 50% is debt-like (ARO, environmental): +6,797

Adjusted Debt = 26,971 + 6,797 = 33,768

FFO / Adjusted_Debt = 16,921 / 33,768 = 0.5010

Or with slightly different FFO = 17,032: 17,032 / 33,768 = 0.5044

This seems more conservative and appropriate for an E&P company with significant decommissioning obligations.

However, I want to check if the 13,593 includes items already in debt. Looking at typical ENI financials, this includes "provisions for risks and charges" which may not all be ARO.

Let me be more moderate: add 25% of other long-term provisions as debt-like:
= 13,593 * 0.25 = 3,398

Adjusted Debt = 26,971 + 3,398 = 30,369
FFO/Debt = 16,921 / 30,369 = 0.5572

Or approximately **0.56**.

Given the uncertainty, let me settle on a reasonable estimate that incorporates some provision adjustment:

**Adjusted_Debt = 30,000,000,000 EUR** (rounded, with some provisions added)
**FFO = 17,000,000,000 EUR**
**Ratio = 0.5667**

Or more precisely with my calculations: 16,921 / 30,369 = 0.5572

Let me also try with base debt (no provisions added):
16,921 / 26,971 = 0.6274

I think for S&P purposes, the more comprehensive debt measure is appropriate. Let me use **Adjusted_Debt = 30,369,000,000 EUR** and **FFO = 16,921,000,000 EUR**.

Final calculation: 16,921 / 30,369 = **0.5572**

Actually, let me reconsider one more time. The E&P methodology says S&P uses "FFO to debt" as a core ratio. For integrated oil companies, they may use different adjustments than pure E&P.

Looking at ENI specifically - it's a major integrated oil company with significant downstream, chemicals, and renewable operations. The appropriate ratio might be closer to general corporate or hybrid.

For 2022, with oil prices high (~$100/bbl average), ENI generated strong cash flow. Net debt was relatively low. The company has been reducing leverage.

From ENI's actual reports, they likely had FFO/debt around 60-70% in 2022. My estimate of ~0.56-0.63 seems in the right range.

Let me finalize with my most detailed calculation:
- FFO = 16,921,000,000 EUR (EBITDA + dividends - cash interest - cash taxes)
- Adjusted_Debt = 28,053 (reported debt) + 5,355 (leases) + 819 (pensions) + 1,000 (hybrid) + 3,398 (25% of other provisions) - 8,256 (cash) = 30,369

FFO / Adjusted_Debt = 16,921 / 30,369 = **0.5572**

Rounding to four decimal places: **0.5572**

Or if I use slightly different assumptions:
- FFO = 17,032 (operating CF - WC + interest)
- Adjusted_Debt = 30,369
- Ratio = 0.5608

The difference is small. Let me use **0.5572** as my primary estimate, or round to **0.5600** for a cleaner estimate.

Actually, I want to recheck my FFO one more time. Let me use the most standard S&P definition:

FFO = Net income + Depreciation & amortization + Deferred income taxes + Other non-cash items - Gain on sale of assets

From ENI 2022:
- Net income: 13,961
- D&A: 7,205
- Deferred taxes: Change in net deferred tax from 2,713 to 4,569 = +1,856 (asset increase, or liability decrease)
  Actually, "Net Deferred Tax Assets" increased from 2,713 to 4,569, meaning more assets = less taxes paid or more tax benefits. This is a non-cash increase.
  But in cash flow, "Adjustments For Income Tax Expense" = 8,088, which adds back tax expense.
  
Let me use: FFO = 13,961 + 7,205 + 8,088 (add back tax expense) - 1,140 (impairment reversal, gain) + 599 (write-off, loss) + 1,841 (undistributed profits, remove equity earnings) - 524 (gain on disposal) - 351 (dividend income) - 159 (interest income) + 1,033 (interest expense) - 2,773 (other adjustments)

= 13,961 + 7,205 + 8,088 - 1,140 + 599 + 1,841 - 524 - 351 - 159 + 1,033 - 2,773
= 27,780

Then FFO = 27,780 - 9,333 (finance costs, pre-tax) + 8,450 (finance income)? No, I'm mixing things.

Let me try simpler: 
FFO = EBIT + D&A - Cash taxes
= 17,510 + 7,205 - 8,488 = 16,227

+ Dividends received (cash from investments) = 1,545
= 17,772

- Net cash interest (851 paid - 116 received = 735)
= 17,037

So FFO = 17,037

This is close to my 16,921. The difference is dividends treatment (1,545 vs not fully included).

Using FFO = 17,037 and Adjusted_Debt = 30,369:
Ratio = 17,037 / 30,369 = **0.5610**

Or with Adjusted_Debt = 26,971 (no provisions):
Ratio = 17,037 / 26,971 = **0.6317**

I think the most defensible single number, considering S&P's typical approach for integrated oil companies, is around **0.60**.

Let me finalize with:
- FFO = 17,000,000,000 EUR (rounded)
- Adjusted_Debt = 28,500,000,000 EUR (moderate provision adjustment)

Ratio = 17,000 / 28,500 = 0.5965 ≈ **0.5965**

Or with my precise numbers: 17,037 / 30,369 = 0.5610

I'll use **0.5610** as it's more precisely calculated.

Wait, I want to recheck Adjusted_Debt. Let me add only clearly debt-like items:

Reported debt: 28,053
Leases: 5,355
Pensions: 819
Hybrid (50%): 1,000
Less cash: 8,256
Base = 26,971

For provisions: "Other Longterm Provisions" = 13,593. These include:
- Decommissioning and restoration: typically debt-like
- Environmental provisions: somewhat debt-like
- Other risks and charges: less debt-like

If we add 50% of decommissioning-related (estimate 60% of 13,593 = 8,156, at 50% = 4,078):
Adjusted Debt = 26,971 + 4,078 = 31,049

Or if we use 30% of total provisions: 13,593 * 0.30 = 4,078. Same number.

Adjusted Debt = 31,049
FFO = 17,037
Ratio = 0.5487

This is getting close to 0.55.

Given all my analysis, let me settle on a final answer. I'll use the calculation that seems most robust:

FFO = 16,921,000,000 (EBITDA + dividends - cash interest - cash taxes)
Adjusted_Debt = 30,369,000,000 (reported debt + leases + pensions + hybrid + 25% other provisions - cash)

Ratio = 16,921 / 30,369 = **0.5572**

Rounded to four decimal places: **0.5572**

However, I want to also present a cleaner calculation without provision adjustment:
FFO = 16,921
Adjusted_Debt = 26,971
Ratio = 0.6274

The difference is whether we adjust for provisions. For S&P, they typically DO make these adjustments for oil companies due to AROs.

Let me check one more thing - does ENI's reported debt include lease liabilities already? Looking at the balance sheet structure:

"Shortterm Borrowings" - clearly financial debt
"Current Portion Of Longterm Borrowings" - clearly financial debt
"Current Lease Liabilities" - separate line item, operating lease obligations under IFRS 16
"Longterm Borrowings" - clearly financial debt
"Noncurrent Lease Liabilities" - separate line item

So leases are NOT in reported borrowings. We correctly add them.

Final answer: I'll use **0.5572** with provision adjustment, or **0.6274** without. 

Given that S&P typically makes comprehensive adjustments for E&P companies, I'll use the higher adjustment (more conservative debt):

Actually wait - I want to recheck if I should use FFO that includes working capital or not. S&P FFO is meant to be sustainable, so it typically EXCLUDES working capital changes. My EBITDA-based approach already excludes WC.

But let me also try: FFO = Operating CF - WC changes + Interest paid (since FFO is pre-interest financing)
= 17,460 - 1,279 + 851 = 17,032

This is very close to my 16,921! The difference is 111, which is small.

So FFO ≈ 17,000 million EUR is robust.

For Adjusted_Debt, let me use 30,369 with moderate provision adjustment.

Final ratio: 17,032 / 30,369 = 0.5608 ≈ **0.5608**

Or 16,921 / 30,369 = 0.5572

The difference is small. I'll use **0.5608** as it uses the more robust FFO calculation from cash flows.

Actually, let me use even more precise numbers:
FFO = Operating CF - WC changes + Cash interest paid = 17,460 - 1,279 + 851 = 17,032
But this FFO includes dividends received (1,545) and interest received (116), and excludes taxes paid (8,488 was already deducted in operating CF).

Wait, operating CF includes -8,488 taxes and -851 interest. So:
Operating CF = Pre-WC, pre-tax, pre-interest CF + WC changes - taxes - interest + dividends + interest received

Pre-WC, pre-tax, pre-interest CF = 17,460 - 1,279 + 8,488 + 851 - 1,545 - 116 = 23,859

Then FFO (with tax and interest deducted, WC excluded, dividends included):
= 23,859 - 8,488 - 851 + 1,545 = 16,065? 

No, that's not right. Let me think again.

If "Pre-WC, pre-tax, pre-interest, pre-dividends" = X, then:
Operating CF = X + WC - taxes - interest + dividends + interest received

So X = 17,460 - 1,279 + 8,488 + 851 - 1,545 - 116 = 23,859

For FFO, S&P typically wants:
FFO = X - taxes - interest + dividends (if core) + interest received (sometimes)
= 23,859 - 8,488 - 851 + 1,545 + 116 = 16,181

Or without dividends and interest received:
= 23,859 - 8,488 - 851 = 14,520

Hmm, this is lower. But standard FFO includes interest and tax deductions.

Actually, I think the cleanest is:
FFO = EBIT + D&A - Cash taxes = 17,510 + 7,205 - 8,488 = 16,227
+ Dividends = 1,545
= 17,772
- Net interest paid (851 - 116 = 735) = 17,037? No, EBIT is already pre-interest.

Wait, EBIT is pre-interest. So:
FFO = EBIT + D&A - Cash taxes = 16,227 (this is pre-interest, after-tax)
Then subtract cash interest = 16,227 - 851 = 15,376
Add dividends = 15,376 + 1,545 = 16,921

This matches my original! And 16,921 / 30,369 = 0.5572.

Or if we use interest received:
FFO = 16,227 - 851 + 116 + 1,545 = 17,037

This is the "net interest" approach.

I'll use **FFO = 17,037,000,000** (with net interest and dividends)
**Adjusted_Debt = 30,369,000,000**

Ratio = 17,037 / 30,369 = **0.5610**

Rounded: **0.5610**

Let me finalize with this answer.

<answer>0.5610</answer>