There seems to be a new superhero movie every month or two this year. We’ve already had “Captain America: The Winter Solider” and “The Amazing Spider-Man 2″ and in a couple of weeks we’ll get the new X-Men film. Quartz has four telling charts that explain the rise in superhero movies since the 80’s, when we had fewer than one a year. Of course the technology that makes it possible to put any super-power or alien planet in a movie is one reason. But this Quartz chart is the one that really matters. Superhero movies are hugely popular overseas. They don’t require English or an understanding of American culture. With China soon to sell more movie tickets to American movies than are sold in the US, we can expect to see a lot more spandex on the screen for the foreseeable future.