64A. Method of calculation of tax to be set off under section 22B or section 22C

Where a registered dealer fails to correlate his purchases of inputs, which have been used directly and sold by him in West Bengal, with the finished goods manufactured and sold by him in West Bengal, the amount of tax to be set off under section 22B or under section 22C may be ; determined by a formula, and for this purpose, formula laid down in rule 64 shall apply mutatis mutandis.