An exemplary method of providing content to users of a social networking service includes determining user-traffic patterns during respective periods of time for a plurality of users on a social networking service in a geographic region. The user-traffic patterns including a first user-traffic pattern during a first period of time. The method further includes selecting a first set of users from the plurality of users in the geographic region to receive personalized content. The personalized content is personalized for respective users in the first set of users. The method further includes setting a first distribution rate for the personalized content during the first period of time based at least in part on the first user-traffic pattern and providing the personalized content to client devices of respective users in the first set of users in accordance with the first distribution rate during the first period of time.