This read-only PerfTotalCount reports the count of frames truncated because the DSL receiver overran and had to cut a frame short, scoped to the running total for the current calendar day so far. Operationally, truncated frames are lost data, and a rising count suggests the receiver is being overwhelmed faster than it can process incoming bits. For example, checking today's running truncated-frame total during a live call lets an admin tell whether the issue the customer is reporting right now has been happening all day.