When the Oscar nominations were announced last month, revealing that not one black actor was in the running, the resulting furor touched on the performances that critics said should have been considered: What about Idris Elba in “Beasts of No Nation”? Michael B. Jordan in “Creed”? Will Smith in “Concussion,” or one of the stars of “Straight Outta Compton”?

The uproar over #OscarsSoWhite made me curious. What does the Academy of Motion Picture Arts and Sciences value in black performance? Black artists have been nominated for best actress or actor on 30 occasions, for work spanning 28 films. Over the last few weeks, I watched all of them.

These are movies with a lot in common, not least that most were written and directed by white men. Only three were written and directed by black men. None were directed by women. Perhaps these numbers aren’t surprising, given the well-known demographics of the film industry. Other numbers are more eye-opening.