This read-only PerfTotalCount reports the count of octets (bytes) received in valid frames on the DSL port, scoped to the most recent rolling 24-hour period ending at the moment of the poll. Operationally, it's the byte-level counterpart to the valid-frame count and lets an admin estimate actual downstream data volume rather than just frame counts. For example, an admin pulling this rolling 24-hour received-octet total can compute a full day's downstream data volume for capacity planning regardless of when the report runs.