Which key metric would provide the most valuable data to the senior management of a financial institution about the effectiveness of its AML controls?

While the number of alerts can indicate activity, it does not reflect the effectiveness of AML controls. A high number of alerts could suggest either effective monitoring or an excessively sensitive system generating many false alarms. Therefore, this metric alone does not assess the true performance of the AML controls.

This metric focuses on customer acquisition rather than the effectiveness of AML controls. It does not provide information about the institution's ability to monitor or mitigate risks associated with those customers once they are onboarded. Thus, it is not a direct measure of the performance of AML efforts.

While exiting clients may indicate risk management practices, this metric is not specifically tied to AML control effectiveness. It does not provide insights into how well the institution is detecting and preventing money laundering activities, making it less relevant for evaluating AML performance.