607A.42  Disposition of names drawn.
  The names of prospective jurors who have been drawn and are eligible to serve on the petit or grand jury and who do not serve shall be omitted from the respective ballot box or selection program.
  At the discretion of the court, the jury manager, or the clerk, a person excused from service on one panel may be required to serve on a succeeding panel if the reason for the person’s being excused is authorized under section 607A.6. In counties using an ex officio jury commission, the ballots of jurors who appear and serve during any term of service shall be destroyed. In counties using a jury manager, the names of jurors who appear and serve during any term of service shall be stricken from the selection program.
86 Acts, ch 1108, §50