Base Salary is the total amount an employee is set to earn in a year not including any variable pay (overtime, incentives, bonuses, commissions, benefits etc…), this amount is usually defined in the employee contract / agreement.
Actual Earned Base is the actual base amount paid to an employee in a one year fiscal period, it does not include any variable pay (overtime, incentives, bonuses, commissions, benefits etc…).
Although in most cases the Actual Earned and Base Salary are the same, these numbers can differ based on the amount of hours worked in a year or the number of pay periods in a year.
In addition, Actual Earned Base is usually obtained from payroll records and can be more accurate than an HRIS system that has not been updated with the employees current salary.
Either number (in addition to hourly rate**) can be used to determine the Job Rate based on the information your organization has access to.