esaProbeHistoryMinNegR2PJitter is an unsigned 32-bit value that reports the lowest recorded negative one-way jitter (packet-to-packet delay variation), in microseconds, from the reflector back to the probe, for a completed interval that has already closed and been archived into the rolling history log. Negative (a packet arriving earlier than the one before it) jitter from the reflector back to the probe is exactly the kind of packet-to-packet delay variation that causes stutter in voice and video traffic riding over the same service. For example, pulling this minimum negative jitter from the reflector back to the probe out of an archived bin from the night of a customer complaint lets the technician confirm the best case never crossed a danger threshold, steering the after-the-fact investigation toward an intermittent cause.