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When someone is looking to measure a campaign’s effectiveness at reaching their target audience, some helpful metrics to do this are Reach and Frequency. Reach is the percent of your target audience that has seen your campaign, and Frequency is the average number of times the ad was seen over the course of your campaign by the target audience. Reach and Frequency occur in an inverse relationship to each other at a constant TRP level. Within such a campaign, as Reach goes up, Frequency goes down, and vice versa.
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