Aspects of the subject matter described herein relate to backup up data. In aspects, a backup target determines a degree to which a data set included on the backup target is not backed up on a backup facility. The degree can represent more than just that the data set is completely backed up or is not backed up at all. If the degree satisfies a condition, the backup target utilizes information derived from a backup history of one or more attempted or successfully completed backup sessions between the backup target and the backup facility to determine whether to provide a notification regarding backup state. The backup target also may send the degree and other backup information to a backup facility which may use this information in determining a backup scheme to employ with the backup target.