Weekend reports are in, and with no movies opening superwide, this weekend's top 5 is a slightly rejiggered version of last weekend's top 5. Instead of 1) Harry Potter, 2) Tangled, 3) Megamind, 4) Burlesque, 5) Unstoppable, it's 1) Tangled, 2) Harry Potter, 3) Burlesque, 4) Unstoppable, 5) Love and Other Drugs. (“Megamind” dropped 238 theaters in the interim.)

So it's a good weekend to talk about legs. As in movies that last. We're in the 12th month of the year: Which movies lasted?

My methodology is simple. I take the total box-office take of a film and divide it by its opening weekend. The movies with the best legs tend to make four to five times their opening-weekend haul; the worst can't even duplicate their opening weekend.

I've discounted films that open on Wednesdays (“Twilight: Eclipse”), since their opening weekend is weaker, making their legs look better, as well as movies that opened in limited release and then went wide (“Hereafter”). A film's opening release should be within spitting range of its widest release.

I eliminated “The Girl Who Played with Fire,” for example. In terms of legs, it's got 'em, grossing more than eight times its opening-weekend box office of $904,000. But its widest release (185 theaters) is almost twice its opening release (108 theaters) and that's not spitting range. (Discussion for another time: only 185 theaters? Isn't Music Box Films being cautious with a movie based on one of the most talked-about books of the 21st century? Or is it not their choice?)

So, given those parameters, here are the movies with the best legs of 2010:

Kind of what we expected. You've got your kids movies (“Dragon,” “Despicable”), movies for older folks who don't rush to movies (“Secretariat,” “Red”), movies for girls (“The Runaways,” “Letters to Juliet”), and the critically acclaimed (“Inception,” “The Social Network”). What you don't have, what you can't have, are sequels. Sequels draw opening weekend. The audience is already there, it doesn't have to be encouraged to get there. (In case you're wondering, the 2010 sequel with the longest legs is “Toy Story 3,” which opened with $110 million and still grossed 3.76 times that number. It's why it's the no. 1 movie of the year.)

As for the worst legs? I've eliminated November releases since they haven't had a chance to outdistance their opening-weekend take yet. (But I'm watching you, “Skyline.”) Here they are:

Again, kind of expected. Horror movies (“Elm Street,” “Wolfman,” “Daybreakers,” “Exorcism,” “Saw 3D”) tend to decompose quickly. They basically appeal to one demographic. “Jonah Hex” was a famous bust (and a semi-horror film, now that I think about it), so that's no surprise, either. I almost took “Valentine's Day” and “The Wolfman” off the list because they opened on a four-day weekend, a kind of holiday weekend, but the above numbers are only through its opening Sunday. So they stayed.

But look at that. Five of these movies couldn't even double their opening weekend take. The horror, the horror.

In the end, the films in the first table just tend to be better than the films in the second table. As measured by the top critics of Rotten Tomatoes, Table A films averaged a 63.5% rating (from “The Social Network” at 100% to “Grown Ups” at 10%), while Table B films averaged a 28.9% rating (from “The Last Exorcism” at 71% to “Jonah Hex” at 7%).