To maintain a separate account for each individual member and annuitant; to maintain adequate accounting records which shall reflect the financial condition of the system, and such additional data as shall be necessary for required calculations, actuarial valuations, and operation of the system; to have the records of the system photographed, microfilmed or otherwise reproduced, which photographs, microfilms or reproductions shall be deemed original records for all purposes.
40 ILCS 5/16-173