Central office expenses—Accounts 6210, 6220, and 6230.

(a) The expenses related to central office equipment are summarized in the following accounts: Table 1 to Paragraph ( a ) Central Office Switching Expense Account 6210. Operator Systems Expense Account 6220. Central Office Transmission Expense Account 6230. (b) The expenses in these accounts are apportioned among the operations on the basis of the separation of the investments in central office equipment—Accounts 2210, 2220 and 2230, combined. [52 FR 17229, May 6, 1987, as amended at 69 FR 12552, Mar. 17, 2004; 83 FR 63586, Dec. 11, 2018]