Performance materiality (which, as defined, is one or more amounts) is set to reduce to an appropriately low level the probability that the aggregate of uncorrected and undetected misstatements in the financial statements exceeds materiality for the financial statements as a whole. Similarly, performance materiality relating to a materiality level determined for a particular class of transactions, account balance, or disclosure is set to reduce to an appropriately low level the probability that the aggregate of uncorrected and undetected misstatements in that particular class of transactions, account balance, or disclosure exceeds the materiality level for that particular class of transactions, account balance, or disclosure. The determination of performance materiality is not a simple mechanical calculation and involves the exercise of professional judgment. It is affected by the auditor’s understanding of the entity, updated during the performance of the risk assessment procedures, and the nature and extent of misstatements identified in previous audits and, thereby, the auditor’s expectations regarding misstatements in the current period. 请翻译成中文