Today, Muggles everywhere are rejoicing at the release, finally, of Harry Potter and the Half-Blood Prince, the sixth movie in the series, based on J.K. Rowling's penultimate book. Half-Blood Prince director David Yates will be helming the crucial final two films in the saga as well — splitting the final book in half — and so, as we near the end of the saga, it's worth asking, where does Half-Blood Prince fit into the Potter pantheon?

Plenty of factors affect the quality of a Harry Potter movie. How much does Ron ham it up, and how adorable is Hermione? How scary is the villain? How many Mike Leigh regulars appear in the cast? What's the Snape-to-Hagrid Ratio? Is Dobby in it? We set Vulture's crack team of Nobel Prize–winning pop-culture mathematicians to task working out the best and worst of the Harry Potter movies thus far.

Related: David Edelstein's review of Half-Blood Prince [NYM]
Fug Girls: In Praise of Emma Watson [The Cut]