definiens: mean complete and accurate records showing clearly all transactions that are relevant to any sales, costs, expenses and payments under this Agreement, to be kept in a manner consistent with generally accepted accounting principles and standard operating procedures . MAYO shall have the right, at its expense, through a certified public accountant or like person reasonably acceptable to NILE, to examine the records of NILE and its Sublicensees during regular business hours before the Termination or expiration ofthis Agreement and for three ( 3 ) years thereafter, provided that such examination shall not take place more often than once a year and shall be limited to a report on the accuracy of royalty statements and payments . If the audit report for any License Year discloses an underpayment discrepancy in royalties owed by NILE and royalties paid by NILE to MAYO that exceeds five percent ( 5 % ) of total Net Sales or Sublicense Revenue made until the date of completion of the audit, NILE shall pay the reasonable expense of the audit and pay to MAYO the entire amount of the discrepancy plus interest within thirty ( 30 ) days from the date upon which MAYO notified NILE of the discrepancy . Interest shall be computed at the rate which is the prime rate of Citibank N.A