This read-only PerfTotalCount reports the count of unaligned frames received on the DSL port, scoped to the most recent rolling 24-hour period ending at the moment of the poll. Operationally, alignment errors mean incoming bits aren't lining up on proper frame boundaries, typically caused by line noise or synchronization problems. For example, a scheduled monitoring job pulling this rolling 24-hour alignment-error total at any time of day still gets a full day's worth of data for trend analysis.