A social networking system generates a feed of content items for presentation to a user based on measures of relevance of the content items to the user at a time when the feed is to be presented and at one or more future times. Content items are associated with value functions representing measures of relevance of the content items to the user over time. Based on the value functions for various content items, the social networking system determines an expected amount of user interaction with the feed when the feed is to be presented as well as predicted amounts of user interaction with the feed at one or more future times. Content items are selected for inclusion in the feed to maximize a combination of the expected amount of user interaction and the predicted amounts of user interaction with the feed.