If you have been reading any gaming news today, you've probably stumbled on one of dozens of articles headlined by the "fact" that sales of the Xbox 360 version of Red Dead Redemption are "up over 6,000 percent" at Amazon. The apparent cause: Rockstar confirming Tuesday that the game would be backward compatible with the Xbox One starting on Friday, July 8.

These two pieces of news are being taken together as evidence that the Xbox One's backward compatibility feature is immensely popular and that untold hordes of Xbox One owners (who apparently don't own a copy of the game for a last-generation system) have been clamoring for a chance to play Rockstar's 2010 Western classic. When you dig into the story a bit, though, the numbers aren't so clear cut.

First, you have to realize that Amazon's much-cited "Movers and Shakers" rankings, which are the source of all of these stories, don't actually measure sales increases directly (thanks to Twitter user ZhugeEX for pointing this out to me). The big, green numbers that the media is quick to hype actually measure the relative increase in sales ranking position, which doesn't correlate directly to actual unit sales levels.

You can confirm this yourself if you plug in the numbers Amazon provides on the "Movers and Shakers" page. As of this writing, for instance, Amazon says that the RDR GOTY edition moved from rank 1,583 to rank 22. Divide 1,583 by 22 and you get 71.95. Subtract one (for the current ranking), and you get 70.95, or the very "7,095 percent" increase indicated by the big green number. The same basic equation works out for every other percentage increase listed on the page.

To be sure, moving up the sales charts by hundreds or thousands of ranking positions in a short period of time is impressive, and that seems to reflect a substantial relative increase in demand for Red Dead Redemption in recent days. But again, this doesn't necessarily mean RDR is selling 60 or 70 times as well as it was just a few days ago.

We really have no idea how impressive that ordinal ranking increase is on a strict "units sold" or relative percentage basis. A sales rank of 22, for instance, could mean 20 or 50 or 100 or more sales a day on a site like Amazon. A sales rank of 1,583 could mean 10 sales a day or 1 sale a day or even less on average. Or, all of those guesses I just made could be way off! We have no way to even estimate the relationship between sales and rankings, since Amazon holds its actual sales data very close to its chest (though some have tried to guesstimate the ranking-to-sales relationship for books).

Given all that, classifying ranking increases in percentage terms is incredibly misleading (and, as we've seen, incredibly likely to be misinterpreted in sloppy media reports). And thanks to the way long tail sales rankings work, a "100 percent increase" from rank 2,000 to rank 1,000 is likely worth much less in actual sales than the same increase from rank 40 to rank 20. Ars' own Steam Gauge data definitely bears out the varying sales distances between relative sales ranks at different points on the curve.

This isn't the first time the media and industry watchers have erred in reporting Amazon sales rank data. Back in March, many sites misinterpreted Amazon's reported jump in sales for the PlayStation Camera and PlayStation Move controller in the wake of Sony's PlayStation VR announcement. Sales for PS3 card game Eye of Judgment apparently shot up 1,300 percent in a single day in 2007. And who could forget when PlayStation 3 sales apparently jumped 641,200 percent in a single day (a number that was definitely not borne out by actual monthly sales reports).

On top of all this, Amazon remains only a small part of the video game market. Data from other online resellers makes it hard to believe that demand for used copies of Red Dead Redemption has actually been multiplied by a factor of 60 or 70 in recent days. The listings over at PriceCharting.com, which tracks used prices around the Internet, show a barely noticeable bump in the game's average asking price in recent days.

A quick search of recently closed auction listings on eBay shows no discernible change in selling price the days before and since the July 5 backward compatibility announcement: the game generally sells between $5 and $15 in both periods, depending on the edition, condition, inclusion of a box/instruction booklet, etc. That's not too surprising when you consider that a downloadable Xbox 360 version of the game is also available for $10.49 (or less for Xbox Live Gold members).

If demand for Red Dead Redemption were actually up by thousands of percentage points in a number of days, we'd likely see prices driven up on other resale marketplaces. Instead, it seems to be business as usual.

On the other hand, the total number of completed, Buy It Now eBay sales for Red Dead Redemption does seem to have ticked up noticeably on July 5. Perhaps the increased demand is being balanced by an increased supply of people selling their used discs in the wake of Rockstar's announcement. Considering the game shipped more than 14 million copies across all platforms, there are definitely plenty of discs out there for people to sell. In any case, the increase in eBay supply is currently closer to a factor of two or three than a factor of 60.

To be clear, there's definite evidence that Red Dead Redemption coming to the Xbox One via backward compatibility has led to increased interest in used copies of the game. But don't believe the headlines that suggest the demand has skyrocketed by a factor of 60 or more. They're based on a faulty understanding of the actual numbers being reported.