Pressure-mixing audit of the BaThF6 COD series (7014520-37): the borderline "NTE" (-90±85 ppm/K) came from grouping by celltemperature while ignoring cellpressure. Ambient-pressure cells give clean PTE, +46.2 ppm/K (150-293 K).
One more artifact class turned up while pruning the spark list, and it's a different disea...