Per its DESCRIPTION, this Counter64 counts one-second intervals where the DS3 P-bit error density crossed the severity threshold. Because this row is the short interval still actively filling right now, a reading here means P-bit-layer errors from the far end clustered badly enough in one second to count as severe on this DS3 circuit, and because the interval has not closed yet, the count will keep climbing until it does and rolls into the history table. For example, a reading of 2 severely errored seconds here, rising in step with Pcv/Pes on the same row, points at a far-end framing problem rather than anything on the near-end line side.