Computation of advance tax: tax on specified sum minus tax deductible or collectible at source, with prescribed agricultural income inclusion. Advance tax is computed as tax on the specified sum less amounts of tax expected to be deducted or collected at source during the financial year, where such income is included in the specified sum and treated as deducted or collected only if paid, credited, received or debited after deduction or collection; when the Finance Act requires, net agricultural income must be taken into account either as the amount used for charging tax in Assessing Officer orders or as the assessee's estimate in other cases.