Described is a technology by which software instrumentation data collected from user program sessions are analyzed, including by determining program usage metrics and/or command usage metrics. Information representative of the program usage metrics and/or the command usage metrics is output, such as in the form of a report. The software instrumentation data may be further analyzed, such as to determine at least one usage trend over time, and to determine user groups. For example, a usage subset of sessions that meet specified session usage criteria based on a set of session data may be located, along with a subset of users based on users whose sessions meet specified user criteria. The usage and user subsets may be combined via Boolean logic to produce a result set.