This Counter64 field reports the bytes transmitted per second on the reverse direction of this bidirectional CES tunnel, as computed for this PM instance. Because this is today's still-open 24-hour PM window, which keeps growing through the day and resets only when the daily boundary rolls over, and this specific field is an instantaneous computed rate of transmitted egress traffic rather than a running total, so a spike here shows up the moment it happens rather than only after the interval ends, it is the field to check when you need to see the reverse-direction egress throughput of the tunnel right now rather than a cumulative volume. For example, this counter might read 5,270 bytes/sec during today's still-running 24-hour bin — a sudden jump to several times that on the reverse side, with no matching rise on the other direction, would point to a one-way traffic surge or an attack riding that leg of the tunnel.