An online system receives information describing a target group of online system users from a third party system and stores the information describing the target group. The online system subsequently uses the target group to select content for presentation to one or more users. For example, users included in the target group are identified as eligible to be presented with content items. Based on revenue obtained by the online system from presenting content based on the target group, the online system determines a monetization value for the target group. The online system determines whether to continue storing the information describing the target group based on the monetization value.