
IMDb reports that Warner Bros. faced a big drop in revenue for 2006. While we can imagine what rationale WB and the MPAA would offer for this revenue drop, IMDb offers another solution:
2005: Charlie and the Chocolate Factory
2006: Poseidon
2005: Harry Potter
2006: Ant Bully
2005: Batman Begins
2006: Lady in the Water
By the way, Lady in the Water is by far the worst movie I have ever seen. It exists in that realm between good movies and movies that are so bad that they are humorous for their badness. Please don't see it.