Well I wouldn't consider a2 a flop. It certainly is underwhelming as it will be finishing more than half a billion WW behind the 1st films of the original run ( I'm using @NCsoft 2.26b ww as the number I'm going off here.)
Hopefully this stops people from making insane predictions ( looking at you @IronJimbo ) for the 3rd film. Had the franchise not disappeared from the public for a decade and treated on the same level as star wars 3-3.5 billion would have been certain.
P.s. Yes by this logic BP2 was also underwhelming. Which I agree with