To estimate the Net Debt to EBITDA ratio for Bouygues at the end of 2022 using the S&P methodology, we need to determine the S&P Adjusted Net Debt and the S&P Adjusted EBITDA based on the provided data.

**1. S&P Adjusted Net Debt**
S&P standard methodology explicitly capitalizes operating leases by including lease liabilities in the total debt, while giving full credit to accessible cash and cash equivalents. 
First, let's look at Bouygues' reported "Net Debt":
* Reported Net Debt = 7,440,000,000 EUR
* *Note: French corporates often report a Net Financial Debt that excludes lease liabilities. We can verify this: Gross Borrowings (11,586 + 1,361 + 418 = 13,365) minus Cash (5,736) minus Net Hedging Assets (193 - 4 = 189) perfectly equals the reported 7,440.*

To align with S&P's standard adjustments, we add the lease liabilities to this reported Net Debt figure:
* Noncurrent Lease Liabilities = 2,107,000,000 EUR
* Current Lease Liabilities = 498,000,000 EUR
* Total Lease Liabilities = 2,605,000,000 EUR

S&P Adjusted Net Debt = 7,440 + 2,605 = 10,045,000,000 EUR

**2. S&P Adjusted EBITDA**
S&P Adjusted EBITDA begins with recurring operating profit and adds back standard non-cash charges such as Depreciation and Amortization (D&A) and impairments. 
* Profit Loss From Operating Activities Recurring (Recurring EBIT) = 1,962,000,000 EUR
* Depreciation and Amortisation Expense = 2,228,000,000 EUR
* Depreciation Right-of-Use Assets = 446,000,000 EUR
* Impairment Loss = 172,000,000 EUR

*(Note: We use Recurring EBIT because S&P typically adjusts out non-recurring, one-off operating items, which in this year were a net expense of 90M EUR).*

S&P Adjusted EBITDA = 1,962 + 2,228 + 446 + 172 = 4,808,000,000 EUR

**3. Net Debt / EBITDA Ratio**
Ratio = S&P Adjusted Net Debt / S&P Adjusted EBITDA
Ratio = 10,045,000,000 / 4,808,000,000 = 2.089 

Rounding to one decimal place, the estimated ratio is 2.1. *(Note: This ratio saw a jump in 2022 due to the acquisition of Equans in Q4 2022, which significantly increased debt without yet providing a full 12 months of trailing EBITDA).*

<answer>2.1</answer>