Concessional customs duty rule applies, reduced customs duties used to compute excise on DTA clearances from EOUs. Excise on DTA clearances from 100% EOU/EPZ units is computed by reference to customs duties on like imports, except that 50% of each basic and auxiliary customs duty is the effective chargeable amount under the exemption notifications. For determining additional customs duty under the Customs Tariff Act, the Section 14 customs value must be increased by these concessional basic and auxiliary duties, and additional duty is then computed on that augmented value. The Board instructs field formations to follow the Method A example for assessment.