This PerfCounter64 counter reports the bits received after rate limiting in the most recent 1-second sample on the access-side port, from the sum of Bytes-Out across all policers times 8, in the upstream (subscriber-to-network) direction (measured after the flow's rate limiter, so it reflects the shaped, delivered rate rather than raw demand). An admin compares it against the subscriber flow's provisioned capacity to see whether traffic is running near, over, or well under what the port or flow is supposed to carry. If cmFlowHistoryIBRRlA2N on flow 1 settles around 768 Mbps at the most recent completed bin, an operator sizing that flow for an upgrade has a concrete number to compare against its provisioned limit, rather than guessing from aggregate port utilization.