Some embodiments provide a scalable framework to retrieve statistics relating different aggregated entities. In some embodiments, the aggregated entity is a pair of ports. The pair of ports can be physical ports of one or more physical forwarding elements. The pair of ports can be logical ports of one or more logical forwarding elements. In some embodiments, the aggregated entity is a machine or a group of machines. In some embodiments, the aggregated entity is an access control list (ACL).