Share is an audience measurement term that identifies the percentage of television households with sets in use which are viewing a particular program during a given time period. If the total TV audience is represented by a pie, the audience for each program is a slice or share of that pie. The slices are not equal... since audience share varies widely according to the relative popularity of each program. Share is a comparative tool; it allows station and network executives to determine how well their programs are doing when compared with competing programs on other broadcast or cable channels.