This counter reports the total bytes of ingress traffic on this PM instance that exceeded even the excess rate and were outright discarded, during a completed 15-minute window (for example 14:30-14:45). Any nonzero value accumulated over that completed 15-minute interval represents traffic this specific service actually lost at ingress due to rate policing, which is a direct, quantifiable cause for a customer's throughput or application-quality complaint on this port, distinct from congestion elsewhere in the network. For example, if this counter shows 50,000 dropped bytes within that completed 15-minute interval right when a customer reports a large file transfer stalling, that strongly suggests their traffic burst past the service's excess rate rather than the file server itself being at fault.