Financial crime risk requires ongoing monitoring and risk ratings should reflect changes in the degree of risk as it evolves due to changes in the client's business ownership and scope of operations. Rating changes can be made during periodic reviews or trigger reviews, where the trigger could be an unusual transaction or receipt of new information about the client. If a client requests a new financial product or service, it may increase the client's financial crime risk rating. Financial crime compliance should be tasked with reconsidering the client's risk rating and should be a signatory to new product approvals. Rules-based transaction monitoring can provide reports of potentially unusual transactions that can be reviewed and escalated by risk managers. For example, setting a customized threshold for transaction value will generate a report of transactions that are unusually large for the client. Periodic account activity reviews, or an opportunity to look at the totality of client transactions during the period, and to consider whether the client is using the account in the way the firm expects for the purposes that the client described during account opening. If a transaction has circular cash flows or appears to achieve no economic effect, for example, buying and selling a security at the same price, it fails the commercial purpose test and the firm should ask for an explanation from the client to satisfy itself that the purpose is not layering.