What does rCPM take into account when determining the value of an ad space?

rCPM, or Revenue Cost Per Mille, measures the revenue generated from an advertisement per one thousand impressions. This metric provides a clearer view of how much value an ad space generates by taking into account total impressions. Total impressions include both paid and organic visibility, reflecting the overall reach of the ad. By considering the total number of impressions, rCPM helps advertisers and publishers understand the performance of ad placements more comprehensively, as it encompasses all opportunities for the ad to be seen.

While the other options touch on different aspects of advertising, they do not fully capture what rCPM assesses. Paid impressions only look at a subset of ad visibility, disregarding the potential reach of organically driven impressions. Ad click-through rates focus specifically on engagement following impression, which is a different performance metric. Organic search traffic, meanwhile, relates more to user engagement from non-paid search results and is not directly relevant to the rCPM calculation. Thus, rCPM's emphasis on total impressions makes it an essential metric for evaluating ad space value.