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support.google.com...]
because it's an estimate...
and, the "below" stat is a live snapshot now, but CTR varies (in competitors ads), among other factors, and when it does, your current bid may get you into the first page auction...
and, if you're close, G might trickle you in, to make sure of their stats (versus them guessing based on past performance)...
and, others may be using dynamic bidding platform tools whose dips may sneak you into the auction, then back out...
and, day parted competitors (check time of day segmentation)...
and, automated rules, like dynamic bid platforms, might be slurping you in and out over time...