This read-only Counter64 counts the total IGMP membership queries received on this PM instance. This is effectively a heartbeat count from the upstream multicast querier — it staying at zero for a whole bin is a first clue that no querier traffic is reaching this port; because it is drawn from this instance's running statistics bin, it behaves like a long-running total rather than a rotating window, so admins baseline against it instead of expecting it to reset daily. On a residential VLAN used for multicast video delivery, a count of 3,447 over the current statistics window is the kind of number an admin would trend against the join/leave rate on the same port to judge whether it's normal channel-surfing or an anomaly worth a closer look.