Relief under section 157(1): form-based computation for additional salary, gratuity, retrenchment compensation, and pension commutation. Form No. 39 prescribes the statement for claiming relief under section 157(1) in respect of additional salary, additional family pension, gratuity, retrenchment compensation and commutation of pension. It requires the assessee's particulars, the relevant tax year, and separate calculations for each receipt by comparing tax on total income with tax on reduced or enhanced income, or by applying the prescribed average-rate method. The form then consolidates the amount of each receipt and the relief admissible and ends with a verification by the assessee.