This counter records the number of frames dropped by the shaper's Random Early Discard congestion-avoidance mechanism during the archived historical interval. A nonzero count here shows an admin that the shaper began proactively dropping frames before its queue was completely full, which is a sign of sustained congestion rather than a single overflow spike. For example, an admin seeing high cmQosShaperHistoryFREDD alongside low cmQosShaperHistoryFTD in the same interval would conclude congestion was managed early and gracefully rather than through hard tail drops.