171.16 MITTIMUS.
   (a)   When the defendant is committed to jail, either to serve a jail sentence or to work out a fine imposed, a mittimus or written order of commitment shall be signed and delivered to the proper officers, or the jailer, or both, as the case may require.
   (b)   Upon expiration of the time covered by such mittimus or order of commitment, there shall be a statement in writing returned to the Court showing the number of days or the time the defendant worked or was confined in jail, either on the back of the said mittimus or commitment, or on a separate paper, which shall be signed by the jailer, or other persons so authorized; and when this report is received it shall be noted on the docket of the case briefly and such report filed away and preserved with the papers of the case.
(1978 Code Sec. 16-17)