20:10:28:14Accounts for the big three expenses -- Plant-specific expenses, plant-nonspecific expenses, and customer operations expenses.

The costs of the general support facilities of class A companies are apportioned among their operations based on the separation of the costs of the combined big three expenses which include the following accounts: (1) Plant-specific expenses: (a) Central office switching expenses, account 6210; (b) Operator systems expenses, account 6220; (c) Central office transmission expenses, account 6230; (d) Information origination/termination expenses, account 6310; (e) Cable and wire facilities expenses, account 6410; (2) Plant-nonspecific expenses: (a) Network operations expenses, account 6530; (3) Customer operations expenses: (a) Marketing, account 6610; (b) Services, account 6620.

Source: 19 SDR 111, effective January 31, 1993.