Sec. 666.1. Structure of the expense accounts

(a) The expense section of the system of accounts shall be organized by expense group summary account, account, and subsidiary record category (if required).

(b) The expense section of this system of accounts shall be comprised of four major expense groups—plant specific operations, plant nonspecific operations, customer operations and corporate operations. Expenses to be recorded in plant specific and plant nonspecific operations expense groups generally reflect cost associated with the various kinds of equipment identified in the plant asset accounts. Expenses to be recorded in the customer operations and corporate operations accounts reflect the costs of, or are associated with, functions performed by people, irrespective of the organization in which any particular function is performed.

(c) Summary accounts within expense groups shall be used to describe aggregations of two or more accounts having a certain commonality. Summary accounts are assigned numbers so that they may be used by telephone companies to aggregate accounts for reporting purposes.

(d) Accounts shall be maintained as prescribed in this uniform system of accounts subject to the conditions described in section 661.3 of this Title. Subsidiary record categories may be required below the account level by this system of accounts or by commission order.