23. Calculation for seventh accounting year:––

For the seventh accounting year, set on or set off, as the case may be, shall be made under clause (ii) of sub-section (7) of section 26, in the manner illustrated in Appendix A, taking into account the excess or deficiency, if any, as the case may be, of the allocable surplus set on or set off in respect of the fifth, sixth and seventh accounting years.