Per its DESCRIPTION, this Counter64 counts seconds during which the DS3 framing pattern could not be found (Severely Errored Framing). Because this row is one of the already-completed short intervals rather than the one still filling, a reading here means the DS3 receiver briefly lost frame alignment and had to resynchronize 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 4 seconds in this bin on this DS3 circuit spiking briefly during a known maintenance window is expected; the same spike with no maintenance scheduled is not.