This PerfCounter64 counts Path Failure Count encountered by an E1/T1 interface in the current bin, i.e. the number of discrete path-layer failure events declared so far. An admin uses this live failure count, distinct from the errored-second counters, to see how many separate outage events (rather than cumulative error duration) the circuit has already suffered this bin. If e1t1StatsPathFCs shows 2 while the bin is only half over, the admin knows this T1 has already flapped twice and may warrant a proactive maintenance dispatch rather than waiting for a third failure.