Security policy efficacy visualization

A management entity communicates over a network with devices on which security rules are configured to control network access. Data that indicates a hit count for each security rule across the devices is repeatedly collected from the devices. The indicated hit counts for each security rule are aggregated over different repeating time intervals to produce repeatedly aggregated hit counts for respective ones of the different repeating time intervals. The security rules are generated for display on a user interface screen as selectable options. Responsive to a selection of one of the security rules, a selected security rule and most recently aggregated hit counts for the different repeating time intervals for the selected security rule are generated for concurrent display on the user interface screen. The display of the most recently aggregated hit counts for the selected security rule is updated as time progresses.