Even Hollywood insiders are completely clueless about Netflix's streaming numbers

Netflix doesn't generally publicly release data about how many or what types of people watch its movies and shows, and it doesn't need to.

That's because Netflix, unlike traditional TV networks, doesn't sell ad time or get subscription fees from cable companies, both of which depend on ratings. And Netflix has decided that, at least for now, it's better off keeping those numbers close to its chest. Or as "Beasts of No Nation" director Cary Fukunaga recently told Business Insider: "That's their MO, to not release numbers."

But you might expect that those working within Hollywood have a better idea of Netflix's streaming data. It turns out, however, that they're just about as clueless as the rest of us.

Vulture talked to numerous industry sources who said they know "precious little" about data on who watches their content, and it's left them "frustrated."

"As not transparent as they are to the press, that's how not transparent they are to us," a source involved in producing shows for Netflix said to Vulture. "They would promise all the time to be more transparent. I heard for months, 'We'll give you the [ratings]' … But they'd keep delaying. They wouldn't show us."

Tina Fey has basically admitted as much, saying at a recent conference of the show she co-creates, "Unbreakable Kimmy Schmidt," "We know that [Netflix chief content officer] Ted [Sarandos] is pleased, which is great news, but we don't have any actual numbers."

The sources Vulture quotes say Netflix will sometimes provide vague information about how a show is doing relative to other shows and "basic stuff" like how many people start a program (though not necessarily finish it). Studios that license their own original content for streaming will try to demand this info. But it's relatively meager for the industry, and provided on a "need-to-know basis." Plus, Netflix has partners sign non-disclosure agreements.

One thing's for sure: Netflix would rather keep the emphasis on how critically acclaimed its latest originals, "Master of None" and "Marvel's Jessica Jones," have been, rather than any numbers that are lower than they'd like.