Section 5, Act, 1964, and shall come into force on the first day of Aprl: ment and

(1) Subsection (2) of section 22 of the principal Act is (a) the substitution in the first and second lines of paragraph (a) thereof for the words * during the year of assessment " of the words during the basis period relating to the year of assessment mentioned in of the group."; 8ubsection (1) "; No. 4 Income Tax (Amendment) 1964 (6) by the substitution in the second and third lines of paragraph (b) thereof for the words " during any year preceding the year of assessment" of the words " during the basis periods relating to any of the six ycars of assessment immediately preceding the said year of assessment ", (2) The provisions of subsection (2) of section 22 of the principal Act as amended by this section shall apply to tax chargeable for the year of assessment commencing on the first day of April, 1964, and all subscqucnt years of assessment irrespective of the fact that claims for losses deductible under the terms of that subsection prior to such amendment had already been submitted to the Commissioner before the commencement of this Act.