Arithmetical accuracy in income computation: officers and staff must verify totals; transcription errors attract responsibility. Income-tax Officers must verify the arithmetic accuracy of total income before signing assessment orders and, where totals exceed the prescribed threshold, record amounts in words and figures; clerks computing tax must use the Officer's determined total and Head Clerks/Supervisors must reconcile the total used for tax calculation with that shown in the assessment order. Errors in transcribing or using an incorrect total income are the responsibility of the concerned clerks, Head Clerks and Supervisors, and arithmetic mistakes detected later in specified cases will be treated as gross negligence by the Officer.