The Belasco has not fared that badly of late. Oh sure, it has had its share of bombs. Given that it is a less desirable house, due to its location and second balcony, it quite often has to house the charity case shows that can't get a better booking.
Still, it has had two Tony Award winning play revivals in the past two years - Awake and Sing, and Journey's End (a critical hit, even if audiences stayed away). Julius Caesar, with Denzel Washington, may have been a critical failure, but it was a financial hit. Frankie and Johnny was another financial hit (as long as Edie Falco and Stanley Tucci were in the cast). Ralph Fiennes won a Tony for his Hamlet, which played at the Belasco. Janet McTeer and the revival of A Doll's House also won Tonys there.
Now, if you want a REAL flop house, take a look at the Longacre's recent history. Apart from the limited run of Diana Rigg's Medea, it hasn't had a hit since Children of a Lesser God in 1980.
Begin at the beginning and go on till you come to the end: then stop.