That is a good point. However, 646-1040 =394 PPM difference when Mobil says typical values would be 800/900 so that is a 100 PPM difference between those two additives. A variance of around 200 PPM would be avg difference between this test & Mobil's values. If it showed 800/1000 on the high end or 700/800 on the low side, as an example, it would be more reflective of typical values. This one is quite off IMO. At least on the P additive. Could be high lab variation as well but still.