(1)M1Subject to subsection (4) below, where the trade, profession or vocation has been set up and commenced within the year of assessment, the computation of the profits or gains chargeable to income tax under Case I or Case II of Schedule D shall be made either on the full amount of the profits or gains arising in the year of assessment or according to the average of such period, not being greater than one year, as the case may require and as may be directed by the inspector.
(2)On an appeal to the General or Special Commissioners, the Commissioners shall have jurisdiction to review the inspector’s decision under subsection (1) above.
(3)Where the trade, profession or vocation has been set up and commenced within the year preceding the year of assessment, the computation of the profits or gains chargeable to income tax under Case I or Case II of Schedule D shall be made on the profits or gains for one year from its first being set up.
(4)Subsections (1) to (3) above shall not apply in any case where [F1there is a change in the persons engaged in carrying on a trade, profession or vocation in partnership and] section 113(1) and (2) apply but no election is made under section 113(2), but in such a case the computation of the profits or gains chargeable to income tax under Case I or II of Schedule D for the year of assessment in which the new trade, profession or vocation is treated as having been set up and commenced, and for each of the three years following that year of assessment, shall be made on the full amount of the profits or gains arising in the year of assessment in question.