budget inlcudes employee's salary but employee himself is not eligible to get merit increase

Summary:

IHAC for whom budget calculation includes employee's salary but employee himself is not eligible to get merit increase. I can always set an error in the alert column but is there any other way to achieve the criteria that "Employee merit increase column will not be editable as the employee himself is not eligible for merit increase, but the employee's salary is included in the total budget calculation. (5% for total employee salary across the org)"

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