To estimate S&P's adjusted leverage trend for Naturgy Energy Group SA, we first calculate the Net Debt / EBITDA ratio for the years 2021 (the period ending 2022-01-01) and 2022 (the period ending 2023-01-01).

**Definitions:**
Net Debt = (Longterm Borrowings + Current Borrowings And Current Portion Of Noncurrent Borrowings) - Cash And Cash Equivalents.
EBITDA = Beneficio Bruto De Explotacion Ebitda.

**For 2021 (Data as of 2022-01-01):**
*   Longterm Borrowings: 13,786,000,000
*   Current Borrowings: 1,493,000,000
*   Cash and Cash Equivalents: 3,965,000,000
*   Net Debt 2021 = (13,786,000,000 + 1,493,000,000) - 3,965,000,000 = 11,314,000,000
*   EBITDA (2021-01-01 to 2022-01-01): 3,529,000,000
*   Ratio 2021 = 11,314,000,000 / 3,529,000,000 ≈ 3.206

**For 2022 (Data as of 2023-01-01):**
*   Longterm Borrowings: 12,689,000,000
*   Current Borrowings: 2,110,000,000
*   Cash and Cash Equivalents: 3,985,000,000
*   Net Debt 2022 = (12,689,000,000 + 2,110,000,000) - 3,985,000,000 = 10,814,000,000
*   EBITDA (2022-01-01 to 2023-01-01): 4,954,000,000
*   Ratio 2022 = 10,814,000,000 / 4,954,000,000 ≈ 2.183

**Calculation of the gap:**
*   Difference = Ratio 2022 - Ratio 2021 = 2.183 - 3.206 = -1.023
*   Since the gap is -1.023, which is significantly lower than -0.3 (implying a substantial decrease in the leverage ratio), the trend is Improving.

<answer>Improving</answer>