Exemption for excess sugar production: duty relief where production exceeds historical average, subject to production accounting. Exemption from whole excise duty is provided for sugar produced in a factory during the specified season in excess of the average production for the corresponding seasons of three prior sugar years, applicable to sugars under Sub heading Nos. 1701.31 or 1701.39. Production computation must use Form R.G.1 or Collector specified records, exclude sugar from gur/khandsari/beet, include certain reprocessed in process products, and apply the averaging rule whereby a nil average permits exemption of the entire current production.