ABSTRACT: This Volume is the last in a six volume set that documents guidelines for carrier access billing. It contains definitions for the data elements presented on the Billing Data Tape (and documented in Volume 3 [SR-1872]). Data source, characteristics, default values, valid entries, type of account, associated records and an example for each data element is also included. The updates for this volume include adding an Appendix for the change control history of the document. The Appendix is a work-in-progress with the end goal to provide the history of changes from 2000 - present. CABS modifications presented in revisions of this document are summarized to provide a cumulative history of changes. The Appendix identifies the specific additions, deletions and changes made to the supporting text for CABS elements since January 2000.