M.     "corporate subsidiary" means any person ten percent or more of whose voting securities or other ownership interests are directly owned by a public utility;

N.     "public utility holding company" means an affiliated interest that controls a public utility through the direct or indirect ownership of voting securities of that public utility;

O.     "voting securities" means securities that carry the present right to vote for the election of directors or other members of the governing body ultimately responsible for the management of the organization; and

P.     "future test period" means a twelve-month period beginning no later than the date a proposed rate change is expected to take effect.