This field is the average, as frozen at the moment this historical snapshot was taken, of the per-interval delta values for FCoE frames that arrived on the wire but were discarded before being handed up to the Fibre Channel stack, taken across the retained collection history for this stats object. Admins watch this to separate a genuinely sustained problem from one noisy interval — if DeltaAvg for droppedRx on this interface is climbing, a nonzero value here on an otherwise healthy Ethernet link points specifically at FCoE buffer exhaustion or a lossless-Ethernet/priority-flow-control misconfiguration, rather than a one-off spike. For example, an average of 0 frames per interval sustained over many polling cycles points at a chronic issue rather than a one-time glitch.