In Core, rates can be assigned to employee groups only from the Fee Schedules or Budgets screens. In the Allocation & Forecasting screen, you only can assign hours or units to an employee or employee group. If you want to see the amounts, they are calculated based on the bill rates of the employee.
In order to see the amounts, click on the Forecasting tab and select Amount under the Units drop-down. If there are no time entries submitted against a project, the only amount you will see is in the Scheduled Amount column. This amount is the total of units allocated multiplied by the bill rate of the employees. However, if there are time entries, the time entries will be shown in the Actual Amount column.