If you’ve been playing along with "Jeopardy!" at home every day of the week for the past 30 years – and no one is going to poke fun if you have – then you’ve undoubtedly noticed that some categories pop up far more often than others. And now you can see exactly what the most popular categories have been, thanks to extensive research from Patrick Tullao, who surveyed every "Jeopardy!" episode from 1984-2012. What is “mind-boggling,” Alex

Here’s what the top ten categories are when counting both the regular Jeopardy! round and Double Jeopardy!

1) Before & After
2) Science
3) Literature
4) American History
5) Potpourri
6) World History
7)Word Origins
8) Colleges & Universities
9) History
10) Sports

My guess would have been “Potpourri” taking the top spot, since it’s such a catchall category, but I’m not surprised to see “Before & After” up there, as those are some of the most fun and clever clues that "Jeopardy!" has going for it. It’s shown up 547 times during the surveyed time period, and what makes this such an astounding feat is that “Before & After” wasn’t even introduced as a category until 1997, which gave most of the other categories over a decade to gain an advantage. (“Colleges & Universities” wasn’t added until 1989.) Sports, on the bottom, showed up 342 times between 1984 and 2012, although it has shown up less in recent years, not appearing at all in 2009, 2011 or 2012.

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It’s pretty interesting looking at the graph, which can be found here, and seeing how many times each of these categories was used each year. 1997 was a banner year for repeated category usage, with “History” showing up the most, with 80 instances. Next up are “Science” and “American History,” both of which showed up 79 times. Incidentally, “Before & After” appeared 76 times in 1999, by far the most it was used.

The graph also shows what the most common Final Jeopardy! categories were, and it’s no surprise that it’s basically just a shorter version of the other list, but with “Word Origins” taking the top spot. With 34 instances, it doubles the second most-used Final Jeopardy! category, “American History,” which was used 17 times.

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Wondering what answers pop up most often? The graph also lays that out, showing that contestants are meant to say "China" the most often, as the country was used for 216 correct answers. “Australia” is right behind it with 215, and they’re followed by another 8 locations, from “Japan” to “Chicago” to “Mexico.” That’s insightful, and shows that potential contestants should be on top of their geography skills.  

I have to assume that if I ever appeared on "Jeopardy!" in the next few years, my category lineups wouldn’t feature any of these, and would probably only focus on stuff I’m terrible with, like “Historical Russian Literature,” “Operas About Animals,” and “Guess The Atomic Number.” What’s your favorite "Jeopardy!" category?

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