Temporal scope of section 80GGA restricted to prior year payments ending on or before the specified prior year end, narrowing deduction eligibility. Amendment restricts deduction eligibility in sub section (2) of section 80GGA by substituting the opening words of clauses (c) and (cc) so that qualifying sums are limited to 'any sum paid by the assessee in any previous year ending on or before the 31st day of March, 2002,' effective from the operative date specified in the amendment.