[Code of Federal Regulations] [Title 19, Volume 2] [Revised as of April 1, 2002] From the U.S. Government Printing Office via GPO Access [CITE: 19CFR159.31] [Page 230] TITLE 19--CUSTOMS DUTIES CHAPTER I--UNITED STATES CUSTOMS SERVICE, DEPARTMENT OF THE TREASURY PART 159--LIQUIDATION OF DUTIES--Table of Contents Subpart C--Conversion of Foreign Currency Sec. 159.31 Rates to be used. Except as otherwise specified in this subpart, no rate or rates of exchange shall be used to convert foreign currency for Customs purposes other than a proclaimed rate or certified rate or rates.