Here’s the reasoning step-by-step:

1. **Calculate EBITDA for 2022 and 2023**  
   - EBITDA ≈ Profit from operating activities + Depreciation and amortisation expense  
   - 2022: 991,970,000 + 522,114,000 = **1,514,084,000**  
   - 2023: 961,554,000 + 544,992,000 = **1,506,546,000**

2. **Calculate Net Debt for each year**  
   Net Debt = Noncurrent Financial Liabilities + Current Financial Liabilities – Cash and Cash Equivalents – Other Current Financial Assets (at amortised cost) – Noncurrent Financial Assets (at amortised cost)  

   *For 2022 (2022-01-01 figures):*  
   - Noncurrent Financial Liabilities = 5,953,434,000  
   - Current Financial Liabilities = 2,144,425,000  
   - Cash = 1,574,427,000  
   - Current Financial Assets at Amortised Cost = 25,401,000  
   - Noncurrent Financial Assets at Amortised Cost = 23,942,000  
   Net Debt = 5,953,434,000 + 2,144,425,000 – 1,574,427,000 – 25,401,000 – 23,942,000  
   = **6,474,089,000**

   *For 2023 (2023-01-01 figures):*  
   - Noncurrent Financial Liabilities = 5,543,755,000  
   - Current Financial Liabilities = 1,705,277,000  
   - Cash = 794,824,000  
   - Current Financial Assets at Amortised Cost = 752,505,000  
   - Noncurrent Financial Assets at Amortised Cost = 175,714,000  
   Net Debt = 5,543,755,000 + 1,705,277,000 – 794,824,000 – 752,505,000 – 175,714,000  
   = **5,525,989,000**

3. **Calculate Net Debt / EBITDA**  
   - 2022: 6,474,089,000 / 1,514,084,000 ≈ **4.28x**  
   - 2023: 5,525,989,000 / 1,506,546,000 ≈ **3.67x**

4. **Year-on-year change**  
   - 4.28x – 3.67x = **0.61x decrease** (improvement larger than 0.3x)

5. **Conclusion**: The ratio improved by more than 0.3x, so the trend is *Improving*.

<answer>Improving</answer>