This Counter64 field tallies the frames on the reverse direction of this bidirectional CES tunnel that were forwarded, specifically traffic the device actually transmitted out of the tunnel after policing and queuing decisions had already been applied. Because this is the currently open, still-accumulating measurement interval that keeps climbing until its boundary is reached and it rolls off into the history table, comparing this to the matching RxAccepted counter for the same direction shows whether everything the policer let in on ingress is actually making it out the egress side, and tracking it separately per direction (forward vs. reverse) lets you tell whether a problem is one-sided rather than affecting the whole tunnel. For instance, over the in-progress 15-minute bin this counter might climb by roughly 5,027,183 reverse-direction frames — a step-change in that number right after a config change on this tunnel, with the forward-direction counter unaffected, would tell you the change altered how much forwarded traffic only that one direction is carrying.