47 C.F.R. § 32.6565
Amortization expense—other
(a) This account shall include only the amortization of costs included in Account 2005, Telecommunications plant adjustment.
(b) This account shall also include lump-sum write offs of amounts of plant acquisition adjustment as provided for in § 32.2005(b)(3) of subpart C.
(c) Subsidiary records shall be maintained so as to show the character of the amounts contained in this account.