ARI SHAPIRO, HOST:
OK, Kelly, guess what these people have in common. Ready? Adolf Hitler, Britney Spears, George W. Bush, Jesus and Michael Jackson.
KELLY MCEVERS, HOST:
I have no idea.
SHAPIRO: Their entries are among the most edited pages on Wikipedia.
MCEVERS: Wikipedia, which, of course, turns 15 years old today.
SHAPIRO: Happy birthday, Wikipedia.
MCEVERS: As we know the entries can be edited by anyone. And this week, the website FiveThirtyEight dug up the most edited pages for each year of Wikipedia's existence.
SHAPIRO: The first one is obvious and not really fair - the page that lists deaths in any given year is constantly being updated.
MCEVERS: Yeah, exactly.
SHAPIRO: But put that aside and FiveThirtyEight quantitative editor Andrew Flowers says things get really interesting.
ANDREW FLOWERS: Wikipedia - maybe this is a testament to its broad appeal - really covers all its bases here. So, for example, in 2012, you have the Syrian Civil War right up there with "Gangnam Style" as the two most edited Wikipedia pages.
SHAPIRO: I believe it's "Gangnam Style."
(SOUNDBITE OF SONG, "GANGNAM STYLE")
PSY: (Singing in Korean).
SHAPIRO: That's right - the Korean pop song.
MCEVERS: Right. So it wasn't always this way. In Wikipedia's first year, the entry on creationism was number one with 124 edits. Then it gained steam and...
FLOWERS: There's over 20,000 edits for George W. Bush in 2005.
MCEVERS: George W. Bush is still the most edited Wikipedia entry of all time - 46,000 edits, Ari.
SHAPIRO: Some people get really into editing some obscure Wikipedia pages, and that shows in these numbers. Take last year - after the death page, the most edited one was not about Donald Trump or Star Wars. Here it is - geospatial summary of the high peaks/summits of the Juneau Icefield.
MCEVERS: Of course.
FLOWERS: Which - I don't know about you - I'm not following the geospatial summaries of Alaskan peaks that closely, but a dedicated person and observer who's logging hundreds of edits a day which we found in the early months of 2015 ranked up over 7,000 edits.
MCEVERS: Wow. That's FiveThirtyEight's Andrew Flowers. For more Wikipedia, listen to Weekend Edition tomorrow when we talk to Jimmy Wales, the founder of Wikipedia.
(SOUNDBITE OF SONG, "TOXIC")
BRITNEY SPEARS: Baby, can't you see? I'm calling. A guy like you should wear a warning. Transcript provided by NPR, Copyright NPR.