(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 the business carried on by the undertaking.] [ Substituted by Act 14 of 2001, Section 7, for sub-Section (4) (w.e.f. 1.4.2001).]