10B (4) For the purposes of sub-section (1), the profits derived from export of articles or things or computer software shall be the amount which Bears to the profits of the business of the undertaking, the same proportion as the export turnover in respect of such articles or things or computer software bears to the total turnover of tljie business carried on by the undertaking.”
Though the taxpayer may have written off the expenditure in its books of account over a period say of five years, it must be allowed in its entirety in the year in which it was incurred, if it is revenue expenditure, and if it is wholly and exclusively incurred for the purposes of business(Para 15)
