; U.S. city average) as of September of such previous year. If any amount established under paragraph (1), after application of this paragraph, for a year is not a multiple of $10, it shall be rounded to the nearest multiple of $10. (3) Alternative to WAC The Secretary may, for purposes of making determinations under paragraph (1), in addition to using the wholesale acquisition cost for an applicable drug, use alternative cost measures of such drug, or use such alternative cost measure if the wholesale acquisition cost is not available. (4) Exception A justification under subsection (c) shall not be required for a triggered SPIKE increase described in paragraph (1) of an applicable drug of a manufacturer if— (A) there is any portion of the lookback period described in the respective subparagraph of such paragraph for such increase that is included within the lookback period for another triggered SPIKE increase (or combination of such increases) for which a justification is made under this section for such drug by such manufacturer; or (B) such increase is less than the wholesale acquisition cost (or alternative cost measure specified by the Secretary under paragraph (3)) of such drug during the calendar-year period described in paragraph (1)(A) or the three-calendar-year period described in paragraph (1)(B), as applicable, for such increase, increased by the percentage increase in the consumer price index for all urban consumers (all items