Based on the financial data and the S&P rating methodology provided, here is the assessment of whether VINCI should be advised to issue hybrid bonds in the next 18 months:

**1. Historical Hybrid Issuance & Capital Structure:**
VINCI has no current hybrid bonds in its capital structure, and it has never issued hybrid bonds in the past. As per the guidelines, an entity's historical track record is a strong indicator of its future capital structure decisions. The absence of hybrid bonds signals a deliberate strategic choice by management to rely on traditional equity, robust cash flows, and standard senior debt, meaning there is no existing replacement cycle or appetite for hybrid instruments.

**2. Leverage and Credit Metrics:**
VINCI exhibits a very strong financial risk profile. Its S&P Net Debt to EBITDA ratio for 2022 stands at a low 1.89x, and its FFO to Net Debt ratio is exceptionally strong at 42.21%. Furthermore, Moody's adjusted leverage trend for the company is "Improving." These metrics comfortably position VINCI in the strong investment-grade ("A" range) category. There is no significant leverage pressure that would necessitate the equity credit relief provided by hybrid bonds.

**3. Cash Flow and Liquidity:**
The company’s cash generation and liquidity position are formidable. For the fiscal year ended December 31, 2022, VINCI reported net cash flows from operating activities of €9.39 billion and an extensive cash and cash equivalents buffer of €12.58 billion. These immense liquidity reserves easily cover its ongoing growth investments, M&A, and debt maturities. As a result, the company has extremely low emergency refinancing needs.

**4. Cost of Debt:**
Market data for 2022 shows a steep increase in swap curves and corporate bond yields across the board. Because hybrid bonds sit lower in the capital structure, they command a substantial yield premium (delta) over senior unsecured debt. Issuing hybrid debt in this environment would materially increase VINCI's weighted average cost of capital without offering any necessary credit rating benefits, rendering it an inefficient financing tool for the company.

**Conclusion:**
Given the lack of previous hybrid issuances, strong and improving leverage metrics, excellent cash flow generation, and the unnecessary cost premium associated with subordinated debt, VINCI perfectly fits the criteria for the 0% category. There is no strategic, financial, or ratings-driven rationale for the entity to issue hybrid bonds.

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