To estimate **FFO / Net debt** for 2022, use a common credit-style approximation:

**FFO ≈ Cash flows from operations before working capital changes − cash interest paid − cash taxes paid**

From the data for 2022:
- Cash flows from operations before changes in working capital = **€4,804.3m**
- Interest paid = **€637.7m**
- Income taxes paid = **€557.4m**

So:

\[
\text{FFO} \approx 4{,}804.3 - 637.7 - 557.4 = 3{,}609.2\text{ m EUR}
\]

Next estimate **net debt** at 2022 year-end / 2023-01-01:

Financial debt items:
- Noncurrent financial liabilities excluding concession liabilities = **€19,692.1m**
- Current financial liabilities excluding concession liabilities = **€6,521.4m**
- Noncurrent lease liabilities = **€1,656.2m**
- Current lease liabilities = **€496.5m**
- Bank overdrafts and other cash position items = **€213.6m**

Gross debt:

\[
19{,}692.1 + 6{,}521.4 + 1{,}656.2 + 496.5 + 213.6 = 28{,}579.8\text{ m EUR}
\]

Subtract cash and cash equivalents:
- Cash and cash equivalents = **€9,012.2m**

\[
\text{Net debt} \approx 28{,}579.8 - 9{,}012.2 = 19{,}567.6\text{ m EUR}
\]

Then:

\[
\frac{\text{FFO}}{\text{Net debt}} = \frac{3{,}609.2}{19{,}567.6} \approx 0.1844
\]

So the estimated **FFO / Net debt ratio for 2022** is approximately **18.4%**.

<answer>18.4%</answer>