/sys$common/syshlp/helplib.hlb MONITOR, MONITOR, Command Qualifier Descriptions, /SUMMARY  *Conan The Librarian (sorry for the slow response - running on an old VAX)

       /SUMMARY[=file-spec]
       /NOSUMMARY (default)

    Specifies that an ASCII disk file be created containing
    summary statistics on all data collected for this request.
    If the optional file specification is omitted, it defaults to
    MONITOR.SUM.