This read-only INTEGER (0-99) reports the ratio of received bits per second to line speed for a port during a sample window, in hundredths, and specifically excludes traffic dropped by local filters per sifFilterLocal. An admin relies on this to see genuine inbound load reaching the port rather than an inflated figure padded by filtered junk traffic. If a port shows 90 here even after local filtering is applied, that's a strong sign the inbound link itself, not filtered noise, is the bottleneck.