We don’t have 2023 data in the facts, only 2022 and 2021, so we can estimate the trend from 2021 to 2022.  
First, we need Net Debt and EBITDA for both years.  

**Net Debt calculation** (simplified as long-term borrowings + short-term borrowings + current portion of long-term borrowings – cash and cash equivalents – current financial assets):  

2022:  
Long-term borrowings = 8,835,000,000  
Short-term borrowings = 1,947,000,000  
Current portion = 1,640,000,000  
Cash = 1,566,800,000  
Current financial assets = 980,600,000  
Net Debt 2022 = 8,835,000,000 + 1,947,000,000 + 1,640,000,000 – 1,566,800,000 – 980,600,000 = 9,874,600,000  

2023:  
Long-term borrowings = 8,416,700,000  
Short-term borrowings = 444,100,000  
Current portion = 1,909,300,000  
Cash = 2,155,100,000  
Current financial assets = 255,300,000  
Net Debt 2023 = 8,416,700,000 + 444,100,000 + 1,909,300,000 – 2,155,100,000 – 255,300,000 = 8,359,700,000  

**EBITDA** (Profit from operating activities + Depreciation & Amortisation):  

2022: 1,200,400,000 + 654,400,000 = 1,854,800,000  
2023: 1,333,500,000 + 725,700,000 = 2,059,200,000  

**Net Debt / EBITDA**:  

2022: 9,874,600,000 / 1,854,800,000 ≈ 5.32x  
2023: 8,359,700,000 / 2,059,200,000 ≈ 4.06x  

The ratio dropped by about 1.26x, which is more than 0.3x, meaning an improving trend.  

<answer>Improving</answer>