Amendment to section 80P removes the reference to chargeability under section 18, altering clause (f)'s operative wording. The Income-tax Act amendment deletes the words 'chargeable under section 18' from clause (f) of sub-section (2) of section 80P, thereby changing the statutory criterion tied to chargeability and altering the operative wording of clause (f) with prospective effect from the stated commencement date.