Count Salary Categories

Task: Calculate the number of bank accounts of each salary category. The result table must contain all three categories.

Table: Accounts

+-------------+------+
| Column Name | Type |
+-------------+------+
| account_id  | INT  |
| income      | INT  |
+-------------+------+

Input: Accounts table:

+------------+--------+
| account_id | income |
+------------+--------+
| 3          | 108939 |
| 2          | 12747  |
| 8          | 87709  |
| 6          | 91796  |
+------------+--------+

Output:

+----------------+----------------+
| category       | accounts_count |
+----------------+----------------+
| Average Salary | 0              |
| High Salary    | 3              |
| Low Salary     | 1              |
+----------------+----------------+