19 CFR 159.34: Certified quarterly rate.

(a) Countries for which quarterly rate is certified. For the currency of each of the following foreign countries, there will be published in the Customs Bulletin, for the quarter beginning January 1, and for each quarter thereafter, the rate or rates first certified by the Federal Reserve Bank of New York for such foreign currency for a day in that quarter:

Australia, Austria, Belgium, Brazil, Canada, Denmark, Finland, France, Germany, Hong Kong, India, Iran, Ireland, Italy, Japan, Malaysia, Mexico, Netherlands, New Zealand, Norway, People's Republic of China, Philippines, Portugal, Republic of South Africa, Singapore, Spain, Sri Lanka (Ceylon), Sweden, Switzerland, Thailand, United Kingdom, Venezuela.

(b) When certified quarterly rate is used. The certified quarterly rate established under paragraph (a) of this section shall be used for Customs purposes for any date of exportation within the quarter, except in the following cases:

(1) Proclaimed rate. If a rate has been proclaimed by the Secretary of the Treasury under § 159.33 which does not vary by 5 percent or more from the appropriate certified daily rate, notice of such variance shall be published in the Customs Bulletin and the proclaimed rate shall be used for Customs purposes in connection with merchandise exported on such date.

(2) Certified daily rate. If the certified daily rate for the date of exportation varies by 5 percent or more from the certified quarterly rate, notice of such variation and the rate or rates certified for such day shall be published in the Customs Bulletin, and such certified daily rate shall be used for Customs purposes in connection with merchandise exported on such day.