NEW YORK (AP) — ESPN’s decision to shut down its 3-D channel by the end of the year is the latest sign the format won’t revolutionize entertainment as the industry once hoped.

Troubling signs for 3-D have been on the horizon for a last year or so. ESPN 3D’s audience ratings were below The Nielsen Co.’s measurable threshold, and in March, the Motion Picture Association said box office revenue for 3-D showings in the U.S. and Canada was flat in 2012 from a year earlier at $1.8 billion. The number of 3-D films released in the period dropped by 20 percent.