This sets a threshold, in the object's time unit, for the interval between consecutive metering, billing, pulses, such that if that interval changes by more than this threshold, an event is triggered and reported to the MGC. This exists to catch abnormal billing behavior in near-real time; a metering interval that suddenly shifts significantly can indicate a billing-rate change was applied unexpectedly or a metering fault occurred, and this threshold is what decides how sensitive the gateway is to flagging that for the controlling application. If normal metering pulses arrive every 30 seconds but suddenly jump to every 10 seconds, exceeding this threshold, the gateway would fire an event to the MGC flagging the anomalous billing-rate change for investigation.