A program guide system in which an interactive television program guide is implemented at least partially on user television equipment receives program listings data and real-time data such as sports scores, news data, etc. The real-time data may be stored in a database maintained by the program guide, so that the program guide may access the stored real-time data at a later time. Updated program listings information may be provided to the program guide as part of the data stream in which the real-time data is provided. Unique keys may be generated for the program listings data and real-time data associated with each live event. The keys may be compared at the program guide to determine which program listings correspond to which items of real-time data. Different types of real-time data may be assigned different expiration times. When data has expired it may be removed from the database.