AAA ratio.
(ii) AAA ratio. Except as provided in this paragraph or paragraph (b)(3)(iv) of this section, the term AAA ratio means the fraction of which the numerator is historical AAA and the denominator is the sum of historical AAA and historical AE&P. Notwithstanding the preceding sentence, if the AE&P of the ETSC is less than or equal to zero as of the beginning of a taxable year, then the AAA ratio is one for such year and for all subsequent taxable years of the ETSC period.