The SIZES program is a utility that originally was named FILEN when it was placed into the public domain on December 1983 by Richard A. Robinson.  It was subsequently rearranged on June 6, 1986 by Phil Wheeler and corrected in order to eliminate a program bug.  It was subsequently renamed as SIZES and was enhanced on October 3, 2015 by Ron Wiesen in order to account for the internal File Buffer FB#0 which always is assigned.