ABC Limited has recently suffered a security breach with customers' social security number available on the dark web for sale. The CISO, during the time of the incident, has been fired, and you have…

ABC Limited has recently suffered a security breach with customers' social security number available on the dark web for sale. The CISO, during the time of the incident, has been fired, and you have been hired as the replacement. The analysis of the breach found that the absence of an insider threat program, lack of least privilege policy, and weak access control was to blame. You would like to implement key performance indicators to mitigate the risk. Which metric would meet the requirement?