Deduction on actual payment: certain tax and employer-contribution deductions allowed only when actually paid, preventing double claims. Section 43B provides that specified deductions-taxes or duties payable by the assessee and employer contributions to employee funds-are allowable only in the previous year in which they are actually paid, regardless of the accounting year in which the liability arose; an Explanation precludes a further deduction under this section if such deduction was already allowed in an earlier previous year.