Target rating points (TRPs) quantify the gross rating points achieved by an advertisement or campaign among targeted individuals within a larger population.
TRPs are calculated as a percentage using for the denominator the total target audience and for the numerator the total impressions delivered to the target audience multiplied by 100.
TRPs (%) = Target Impressions (#) ÷ Target Audience (#) x 100
As an example:
1,000,000 impressions among the target audience ÷ 10,000,000 people in total in the target audience x 100 = 10 TRPs
TRPs can also be calculated from GRPs:
TRPs (%) = GRPs X (% of GRPs Delivered to Target / Target % of Population) x 100
Alternatively, TRPs can be calculated using the target specific reach and frequency:
TRPs (%) = Target Reach (%) × Average Target frequency (#)
TRPs are often added up by week and presented in a flowchart so a marketer can see the number delivered to the target audience from each media channel.
Share-Based TRPs, a related concept sometimes colloquially called TRPs, is the estimated proportion of GRPs delivered to the target:
Share-Based TRPs = GRPs X Estimated Percent of GRPs Delivered to Target
The Share-Based TRPs approach may not yield the same result as the traditional calculations of TRPs. In particular, this formulation does not necessarily yield a value equal to the reach times the frequency. It is critical to understand which approach is being used in each application.
- Common Language in Marketing Project, 2021.