This read-only Counter64 counts bytes received on this PM instance that the switch discarded outright, rather than forwarding or yellow-marking them. This is the counter an admin escalates on — sustained non-zero drops mean traffic on this flow point exceeded even the excess-rate allowance or hit a policy/resource limit, and whatever service rides this instance will show real loss; because it is drawn from this instance's running statistics bin, it behaves like a long-running total rather than a rotating window, so admins baseline against it instead of expecting it to reset daily. On a 1 Gbps UNI feeding a business Ethernet Private Line, this might read 578,000 bytes over the current statistics window — a number an admin would divide by the bin length to sanity-check it against the port's 1,000,000,000-bps ceiling.