Per its DESCRIPTION, this Counter64 counts one-second intervals where the DS3 Line-layer error density crossed the severity threshold. Because this row is one of the already-completed short intervals rather than the one still filling, a reading here means the DS3 line had a run of severely errored seconds on this DS3 circuit, within that one specific closed interval, which you can pin to an exact clock window using this row's StartTime and EndTime. For example, a reading of 0 seconds in this bin on this DS3 circuit climbing while Loss stays at zero suggests noise or crosstalk on the copper pair rather than a full disconnect.