Revenue recognition rules for tax computation define transfer of risks, percentage completion for services, and disclosure obligations. Income Computation and Disclosure Standard IV prescribes tax-computation rules for recognising revenue from sale of goods, rendering of services, and use of resources yielding interest, royalties and dividends. Revenue for goods is recognised on transfer of property or significant risks and rewards and subject to reasonable certainty of collection; claims with uncertain collectability are deferred. Services are generally recognised by the percentage completion method (with short-duration contracts recognised on completion), while interest, royalties and dividends are recognised on systematic bases aligned with agreement terms or statutory provisions. Transitional rules and specific disclosures for unrecognised amounts and work in progress are required.