Is it possible to query the salary of terminated employees?

We are trying to report the salaries of terminated employees for ACA. When we run the following query no data is returned. The terminated employees have a 3 month Final Processing date from their Actual termination date on the Terminate form. Is it possible to gather the salary information for a terminated employee?

select change_date, proposed_salary_n
from apps.per_pay_proposals ppp
where
assignment_id = xxxx

Thanks.