(1) In this section -
"the net amount" with which a person is chargeable to tax under section 91 means the amount with which such person is so chargeable after making any deduction authorised by section 91(4) but before giving any relief under this section;
"relevant date" means -
(a) in relation to tax under section 91, the date of the permanent discontinuance, and
(b) in relation to tax under section 94, the date of the change of basis.
(2) Where an individual born before the 6th day of April, 1919, or the personal representative of such an individual, is chargeable to tax under section 91 or 94 and -
(a) the individual was engaged in carrying on the trade or profession on the 4th day of August, 1970, and
(b) the profits or gains of the trade or profession were not computed by reference to earnings in the period in which the date specified in paragraph (a) fell, or in any subsequent period ending before or on the relevant date,
the net amount with which such individual is so chargeab
…