This read-only PerfTotalCount reports the count of frames successfully transmitted on the DSL port, scoped to the full previous calendar day's totals for the DSL port. Operationally, it's the baseline throughput indicator for outbound traffic and confirms the port is actually pushing data toward the customer. For example, comparing yesterday's total transmitted-frame count to prior days lets an admin spot an unusual drop in outbound activity that might correlate with a reported problem.