This image released by Showtime shows Michael C. Hall as Dexter Morgan in a scene from the series finale of "Dexter."  (AP Photo/Showtime, Randy Tepper)If a show you never really liked has a lame finale, well, what did you expect? But if a show is popular and well-respected, and it pulls a "Dexter" in the final episode, then you end up with a massive popularity free-fall, as documented by a Reddit user in a new series of graphs.

Someone called ChallengeResponse recently posted charts ranking TV finales by different metrics, based on IMDb ratings. You can check them out here. The first one shows the ratings of series finales relative to their average episode ranking. Showtime's "Dexter" ended up way at the bottom, because most of the episodes had been rated high, so the average was high going into the finale; fans expected a lot from the final episode, but they hated it so much that its rating dropped more than any other final TV episode. On the flip side, "Glee" is at the top, not because it was considered to have the best finale of all time, but it was a higher rated finale than the average of the show's other episodes. Fans didn't think "Glee" was always a good show, but they thought it ended strong.

The highest finale episode ratings went to "Breaking Bad" and "Dexter" star Michael C. Hall's other show, "Six Feet Under." On that list, just ranking fans' final episode ratings, "Dexter" had the second worst rating, just above "Two and a Half Men." But that sitcom didn't have average episode ratings as high as "Dexter," so its finale was less "disappointing" than "Dexter" or shows like "True Blood" and "How I Met Your Mother," which also had much lower finale ratings than their average IMDb ratings.

All the graphs are over here, if you want to sort through the data.

Do you think "Dexter" deserved the biggest popularity drop for its finale, or would you give that dubious honor to HIMYM, "The Sopranos," "Seinfeld" or another show?

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