on the amount of the deficiency and not on the total amount. (2) If there is any underreporting of royalty owed on production from a claim or lease for any production month by any person liable for royalty payments under this section, the Secretary shall assess a penalty of not greater than 25 percent of the amount of that underreporting. (3) For the purposes of this subsection, the term underreporting means the difference between the royalty on the value of the production that should have been reported and the royalty on the value of the production which was reported, if the value that should have been reported is greater than the value that was reported. (4) The Secretary may waive or reduce the assessment provided in paragraph (2) of this subsection if the person liable for royalty payments under this section corrects the underreporting before the date such person receives notice from the Secretary that an underreporting may have occurred, or before 90 days after the date of the enactment of this section, whichever is later. (5) The Secretary shall waive any portion of an assessment under paragraph (2) of this subsection attributable to that portion of the underreporting for which the person responsible for paying the royalty demonstrates that— (A) such person had written authorization from the Secretary to report royalty on the value of the production on basis on which it was reported