This counter records the number of Severely Errored Seconds accumulated at this flow point during the archived historical interval, a standard telecom metric for seconds with an unusually high error ratio. A rising historical SES count tells the admin that this flow point experienced periods of serious signal or frame-level degradation short of full unavailability, useful for spotting a marginal link before it fails outright. For example, if a customer reports intermittent glitches without full outages, the admin would check cmFlowPointHistorySES for the relevant period to confirm the flow point was experiencing severe error bursts rather than a clean signal.