FFO / Net debt is commonly estimated as:

- **FFO** ≈ cash flow from operating activities before working-capital movements, after interest and taxes paid.
- **Net debt** ≈ financial liabilities minus cash and cash equivalents.

Using the 2022 figures:

**1. Estimate FFO**

The cash flow statement provides a **Subtotal** before working-capital changes of:

- Subtotal 2022 = **€2,516,130,000**

Then adjust for cash interest and taxes:

- Income taxes paid = **€343,100,000**
- Interest paid = **€36,100,000**
- Interest received = **€6,100,000**

Estimated FFO:

\[
FFO = 2{,}516{,}130{,}000 - 343{,}100{,}000 - 36{,}100{,}000 + 6{,}100{,}000
\]

\[
FFO = 2{,}143{,}030{,}000
\]

**2. Estimate net debt at year-end 2022**

Financial liabilities at 2023-01-01:

- Noncurrent financial liabilities = **€2,844,559,000**
- Current financial liabilities = **€1,109,297,000**
- Cash and cash equivalents = **€409,252,000**

\[
Net\ debt = 2{,}844{,}559{,}000 + 1{,}109{,}297{,}000 - 409{,}252{,}000
\]

\[
Net\ debt = 3{,}544{,}604{,}000
\]

**3. FFO / Net debt**

\[
\frac{FFO}{Net\ debt} = \frac{2{,}143{,}030{,}000}{3{,}544{,}604{,}000}
\]

\[
= 0.6046 \approx 60.5\%
\]

<answer>60.5%</answer>