I don't think there's any "real" trend in to the way the tests are going. But I still shouldn't worry about it.
I didn't even do anything to the car to get it "ready" this time, as I usually do (I usually remove & clean the spark plugs, cap & rotor at least).
Oh, wait - not true - I pumped up the tires to 60 psi
. I figured: the less rolling resistance on the dynamometer, the better the results!
But I should just remind myself to come back here and look at the previous results before each test (every other year) to put my mind at ease!