The Format Recognition program was designed for books records cataloged under pre-AACR2 rules and pre-ISBD conventions. The PREMARC file, as noted above, consists of records representing serials, maps, music, filinstrips, motion pictures and sound recordings, as well as books, and all are forced into the books format. Most of these items were cataloged before the implementation of AACRl. The accuracy of the Format Recognition coding was further hindered by data errors. For example, the absence of a period after the abbreviation for "born" in the heading "Hall, Caroline Arabella, b 1838." caused format recognition to tag it as a corporate body rather than a personal name.