To estimate the S&P adjusted leverage trend for VERBUND AG, we need to calculate the Net Debt / EBITDA ratio for the fiscal years ending 2022 (period 2021-01-01 to 2022-01-01) and 2023 (period 2022-01-01 to 2023-01-01).

**Step 1: Identify EBITDA**
From the provided facts:
*   EBITDA 2021 (FY2021): 1,578,959,000 EUR
*   EBITDA 2022 (FY2022): 3,160,679,000 EUR

**Step 2: Calculate Net Debt**
Net Debt is typically defined as Total Financial Liabilities (Current + Noncurrent) minus Cash and Cash Equivalents. We use the balance sheet data at the end of each period.

*   **For Year End 2021 (2022-01-01 balance sheet represents the end of FY2021? No, standard reporting: "2022-01-01" usually refers to the opening balance of 2022 or closing of 2021. Let's look at the labels carefully.**
    *   The facts list "Noncurrent Financial Liabilities" and "Current Financial Liabilities" with dates 2021-01-01, 2022-01-01, and 2023-01-01.
    *   Usually, annual reports provide closing balances.
        *   Date `2021-01-01`: Closing balance of 2020 / Opening 2021.
        *   Date `2022-01-01`: Closing balance of 2021 / Opening 2022.
        *   Date `2023-01-01`: Closing balance of 2022 / Opening 2023.
    *   The EBITDA figures are for periods:
        *   "2021-01-01 - 2022-01-01": This is Fiscal Year 2021. We should pair this with the Net Debt at the end of this period, which is the balance sheet date `2022-01-01`.
        *   "2022-01-01 - 2023-01-01": This is Fiscal Year 2022. We should pair this with the Net Debt at the end of this period, which is the balance sheet date `2023-01-01`.

    *   **Net Debt at 2022-01-01 (End of FY2021):**
        *   Noncurrent Financial Liabilities: 1,834,155,000 EUR
        *   Current Financial Liabilities: 1,462,453,000 EUR
        *   Total Financial Liabilities: 1,834,155,000 + 1,462,453,000 = 3,296,608,000 EUR
        *   Cash and Cash Equivalents: 318,562,000 EUR
        *   Net Debt 2021 = 3,296,608,000 - 318,562,000 = 2,978,046,000 EUR

    *   **Net Debt at 2023-01-01 (End of FY2022):**
        *   Noncurrent Financial Liabilities: 2,844,559,000 EUR
        *   Current Financial Liabilities: 1,109,297,000 EUR
        *   Total Financial Liabilities: 2,844,559,000 + 1,109,297,000 = 3,953,856,000 EUR
        *   Cash and Cash Equivalents: 409,252,000 EUR
        *   Net Debt 2022 = 3,953,856,000 - 409,252,000 = 3,544,604,000 EUR

**Step 3: Calculate Leverage Ratios (Net Debt / EBITDA)**

*   **Leverage 2021 (FY2021):**
    *   Net Debt: 2,978,046,000 EUR
    *   EBITDA: 1,578,959,000 EUR
    *   Ratio = 2,978,046,000 / 1,578,959,000 ≈ **1.89x**

*   **Leverage 2022 (FY2022):**
    *   Net Debt: 3,544,604,000 EUR
    *   EBITDA: 3,160,679,000 EUR
    *   Ratio = 3,544,604,000 / 3,160,679,000 ≈ **1.12x**

**Step 4: Determine the Trend**
*   Change in Ratio = Leverage 2022 - Leverage 2021
*   Change = 1.12x - 1.89x = **-0.77x**

The definition provided states:
*   **Stable**: Gap is among ± 0.3x (i.e., between -0.3x and +0.3x).
*   **Improving**: Gap is lower than 0.3x. Note: In leverage contexts, a *decrease* in leverage is an improvement. The prompt says "if the gap ... is lower than 0.3x is improving". This phrasing is slightly ambiguous. Usually, "lower than -0.3x" would mean a significant drop. Let's re-read carefully: "if the gap of the ratio Net Debt / EBITDA year on year is lower than 0.3x is improving. If higher is Deteriorating."
    *   This likely implies:
        *   Gap < -0.3x: Improving (Leverage went down significantly)
        *   -0.3x <= Gap <= 0.3x: Stable
        *   Gap > 0.3x: Deteriorating (Leverage went up significantly)
    *   Alternatively, it could mean absolute value, but "lower than 0.3x" usually refers to the algebraic value in these automated logic prompts. However, standard financial interpretation:
        *   Leverage dropped from 1.89x to 1.12x. This is a significant reduction in debt relative to earnings. This is a positive credit development.
        *   The gap is -0.77x.
        *   Is -0.77x "lower than 0.3x"? Yes, -0.77 < 0.3.
        *   Does this fit the "Improving" category? Yes, a large negative gap means leverage decreased, which is improving.

Let's double check the "Stable" definition: "gap ... is among ± 0.3x". This means if the change is between -0.3 and +0.3, it is stable.
The change is -0.77. This is outside the stable range.
Since the leverage decreased (negative change), the credit profile is improving.
Therefore, the trend is Improving.

<answer>Improving</answer>