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 the current, still-open 24-hour bin for today, the number keeps climbing until midnight rollover, so it should be read as "so far today" rather than a finished daily total. On a 10 Gbps wholesale handoff port, this might read 4,820,000,000 bytes over today so far — a number an admin would divide by the bin length to sanity-check it against the port's 10,000,000,000-bps ceiling.