The purpose of the “target rating point” metric is to measure impressions in relation to the number of people in a specific target audience for an advertisement. Thus, the TRP is a measure of the purchased points representing an estimate of the component of the target audience within the gross audience. Similar to the gross rating point, it is measured as the sum of ratings achieved by a specific media vehicle (e.g., TV channel or program) of the target audience reached.
Target rating points (TRPs) quantify the gross rated points achieved by an advertisement or campaign among targeted individuals within a larger population. The TRP and GRP metrics are both critical components for determining the marketing effectiveness of a particular advertisement.
Outside of television, TRPs are calculated using the denominator of the total target audience, and the numerator as the total impressions delivered to this audience x 100. (As in 1,000,000 impressions among the target audience ÷ 10,000,000 people in total in the target audience x 100 = 10 TRPs).
Within television, TRPs are either calculated in the same manner or calculated as the sum of individual GRPs multiplied by the estimated target audience in the gross audience. This alternate calculation approach does not yield the same result. So it is critical to understand which approach is being used.
TRPs are often added up by week, and presented in a flowchart so a marketer can see the amount of impressions delivered to the target audience from each media channel.
- ^ Farris, Paul W.; Neil T. Bendle; Phillip E. Pfeifer; and David J. Reibstein (2010). Marketing Metrics: The Definitive Guide to Measuring Marketing Performance (Second Edition). Upper Saddle River, New Jersey: Pearson Education, Inc.