For accounting and classification purposes it is the treaty year in which a contract was written or renewed. Applies to proportional reinsurance. See UNDERWRITING YEAR SYSTEM.
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The calendar year during which the risk attaches on the original Insurance.
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the accounting year of an insurer or Lloyd’s syndicate to which insurance business relates, usually determined by the date of inception; reinsurance contracts may be written by reference to the insurer’s business of a particular underwriting year, and will remain in force until all the claims referable to that underwriting have been settled.