(a) Separate common debit expense accounts in proportion to the assignment of solely related freight or passenger service in each individual debit account. If there are no solely related expenses or if the solely related expenses are assigned entirely to freight or passenger service, separate common debit expense accounts on the same percentage basis calculated for the separation of administration (account XX-26-01).
(b) Separate all common credit expense accounts on the same percentages calculated for the separation of administration (account XX-26-01).