Insurance business profit computation uses actuarial surplus, statutory accounts, investment adjustments, and non-resident premium apportionment rules. Profits of life insurance business are computed separately on the basis of the annual average surplus disclosed by actuarial valuation, with inadmissible expenditure added back and credit for tax deducted at source adjusted for the valuation period. Other insurance business is computed from statutory profit before tax and appropriations, subject to additions back of inadmissible expenditure, investment-related adjustments, and deductions for prescribed reserves and certain later-allowed amounts. For non-resident insurers, profits may be deemed by reference to the ratio of Indian premium income to total premium income. The Schedule also defines investments and life insurance business.