To estimate the FFO / Net Debt ratio for 2022, we need to calculate the Funds From Operations (FFO) and the Net Debt for the year 2022 using the provided financial facts.

**Step 1: Calculate FFO for 2022**
Funds From Operations (FFO) is typically defined as Profit Loss plus Depreciation And Amortisation Expense, plus Adjustments For Finance Costs (interest expense), minus Adjustments For Finance Income (interest income). 
From the data for the period 2022-01-01 to 2023-01-01 (which corresponds to the year 2022):
- Profit Loss: 681,187,000 EUR
- Depreciation And Amortisation Expense: 544,992,000 EUR
- Finance Costs: 116,468,000 EUR
- Finance Income: 23,161,000 EUR

FFO = Profit Loss + Depreciation And Amortisation + Finance Costs - Finance Income
FFO = 681,187,000 + 544,992,000 + 116,468,000 - 23,161,000
FFO = 1,319,486,000 EUR

**Step 2: Calculate Net Debt at the end of 2022**
Net Debt is defined as Total Financial Debt (Current and Non-current Borrowings and Other Financial Liabilities) minus Cash And Cash Equivalents. We use the balance sheet values at the end of 2022 (2023-01-01).

Total Financial Debt includes:
- Longterm Borrowings: 5,491,124,000 EUR
- Other Noncurrent Financial Liabilities: 52,631,000 EUR
- Noncurrent Derivative Financial Liabilities: 22,016,000 EUR
- Current Borrowings And Current Portion Of Noncurrent Borrowings: 721,845,000 EUR
- Other Current Financial Liabilities: 983,432,000 EUR
- Current Derivative Financial Liabilities: 7,053,000 EUR

Total Financial Debt = 5,491,124,000 + 52,631,000 + 22,016,000 + 721,845,000 + 983,432,000 + 7,053,000
Total Financial Debt = 7,278,101,000 EUR

Cash And Cash Equivalents at 2023-01-01: 794,824,000 EUR

Net Debt = Total Financial Debt - Cash And Cash Equivalents
Net Debt = 7,278,101,000 - 794,824,000
Net Debt = 6,483,277,000 EUR

**Step 3: Calculate the FFO / Net Debt ratio**
Ratio = FFO / Net Debt
Ratio = 1,319,486,000 / 6,483,277,000 ≈ 0.203535

Rounding to two decimal places, we get 0.20.

<answer>0.20</answer>