Just what is it about Angelina Jolie? No, not the eight kids and eight-pound lips. We’re talking about her recent track record of openings that’s unusual for a female star and unprecedented for a female action hero.

Most actresses open movies when they’re playing more sedate roles in comedies or dramas, may sort of help open thrillers, and struggle as a pure action lead.

Jolie is exactly the opposite: She’s a can’t-miss in action roles, kind of doesn’t do much in thrillers and tanks in comedies and dramas.

Some numbers:

–Including “Wanted,” she’s now had five leading or co-leading action roles this decade — three earned or will earn over $100 million, and a fourth earned $82 million.

–She’s had three leading or primary roles in thrillers — and averaged only about $36 million in each.

–In her three leading dramatic roles, she hasn’t cracked $15 million.

She’s basically a Julia Roberts for the new age, except while Roberts did it almost exclusively in the realm of rom-coms and weepies, Jolie does it almost exclusively in a realm that’s previously been more verboten to women than the Illuminati.

Some of these gaps can be attributed to the size and expectations of the  movies themselves. But that doesn’t account for the disparity between action movies and thrillers, which shouldn’t on their face be nearly as wide as these numbers suggest. And it’s not like all the dramatic flops were obscure specialty projects either — they include bigger budgeted movies from the likes of Fox (”Life or Something Like It”) and Paramount (”Beyond Borders”).

One exec we talked to today explained the appeal of an action pic that stars Jolie as a movie that can hit to both sides of the field. Not only is Jolie believable as an action hero — which means the target-demo males won’t be put off (and in fact may be turned on) — but with her high Q rating among women she opens up an action movie to female audiences too.

Seems like there’s a lot to that, but there may also be something to this. Anecdotally, filmgoers have said it’s increasingly hard to watch Jolie on the bigscreen because she’s one of those stars whose presence immediately conjures up associations from her personal life (see under: the aforementioned babies).

Now, that may be true when we’re seeing her as a devoted wife or pregnant mom — movies like “A Mighty Heart” or “A Good Shepherd” — and so audiences stay away. But it becomes less of a factor the further you get down the reality spectrum.

As a sort of semi-relatable character in a thriller, she’s able to pull in a few more moviegoers, though she’s still a little too much of, well, Angelina Jolie.

But when she transforms into a completely otherwordly character– a leather-clad, gun-shooting  Fox from “Wanted” or Lara Croft from “Tomb Raider” — then audiences can get into it and turn out for her films.

So basically, one of the biggest movie stars in the world will draw more box office the less she seems like herself. In the upside-down world of Angelina Jolie, that’s just about perfect.