Mario Kart 8 will likely be the worst-selling game in franchise history, here's why

The Mario Kart series has long been a sales leader, ranking as the second-best selling game on Nintendo's last three hardware platforms, but even if every current Wii U owner bought the next installment, Mario Kart 8, it would still be the second-worst selling game in franchise history.

That's because there are only 6.17 million Wii U consoles in gamers' homes, and that's fewer than the number of copies that all but one previous Mario Kart game sold. The only way Mario Kart 8 could sell more would be by driving gamers to buy new consoles. And that's certainly one of the things Nintendo hopes will happen.

In a recent financial report, Nintendo cited Mario Kart 8 and Super Smash Bros. as the Wii U's "two main drivers" for the fiscal year ending March 31, 2015. The company expects to sell another 3.6 million Wii U consoles by the end of the fiscal year, according to Nintendo's consolidated financial statement, bringing the number of Wii U consoles on the market to 9.77 million. But even that wouldn't make Mario Kart 8 the smash hit Mario Kart DS and Mario Kart Wii became.

Polygon examined the last 22 years of Mario Kart games sales. Based on our research, an average of 20.37 percent of those who purchase Nintendo hardware also purchase Mario Kart games. If Mario Kart's trend continues and Nintendo sells Mario Kart 8 to 20.37 percent of its existing 6.17 million user base, sales of the game would reach 1.26 million. If Nintendo's console predictions are correct, and assuming the average of 20.37 percent remains, Mario Kart 8 sales would reach 1.99 million units by the end of March 2015. Meaning this latest Mario Kart would sell a bit more than a third of the copies that the worst-selling Mario Kart, 2001's Mario Kart: Super Circuit for the Game Boy Advance, sold in its lifetime.

Part of the reason this game's potential sales look so comparatively low is because the franchise as a whole is a massive hit.

Since Super Mario Kart was released for the Super Nintendo Entertainment System in 1992, Nintendo has sold 489.83 million hardware units across seven platforms, including three handhelds (Game Boy Advance, Nintendo DS and Nintendo 3DS) and four consoles (Nintendo 64, GameCube, Wii and Wii U). In that same period, the company sold 99.76 million Mario Kart games. The Mario Kart hardware attach rate, which shows what percentage of people who own a piece of Nintendo hardware also purchased a Mario Kart game, averages 20.37 percent over those 22 years.

A note about the numbers we used for this analysis. On its investor website, Nintendo provides sales figures for consoles dating back to the NES as well as top software sales figures for the Wii U, Wii, 3DS and DS. It does not provide software sales information for games before that. We reached out to Nintendo for that information but did not receive it before publication. In lieu of Nintendo's official sales figures, we sourced multiple outlets to find the most accurate figures available. We obtained Super Mario Kart (released in 1992 for Super Nintendo) sales figures of 8.76 million from VGChartz, with additional information released in a 2009 report from the Guinness Book of World Records and an IGN report. For Mario Kart 64 (1996), we obtained sales information from VGChartz (9.87M) with additional information from The Magic Box and an additional report from The Magic Box. For Mario Kart: Super Circuit (2001), VGChartz (5.47M) and The Magic Box. For Mario Kart: Double Dash! (2003), VGChartz (6.95M), the 2009 Guinness report and two separate reports from The Magic Box.

In its first two decades, Mario Kart attach sales ranged from a low of 5.47 million with Mario Kart: Super Circuit to a high of 35.53 million with Mario Kart Wii. Sales were relatively consistent until they more than tripled with the release of Mario Kart DS in 2005 and Mario Kart Wii in 2008 when the attach rate rose to 35.16 percent on the Wii. The attach rate returned to more typical series standards and currently rests at 22.20 percent for Mario Kart 7, which was released in 2011 for Nintendo 3DS.

In October 2013, Nintendo characterized its latest console as having "a negative impact" on profits, particularly because of its "markdown" in Europe and the U.S. In the six-month period preceding the financial report, Nintendo sold 460,000 Wii U units worldwide. Earlier this month, Nintendo announced a $456 million annual operating loss and also reported that "unit sales of software, which has high profit margins, did not grow sufficiently."

Mario Kart games are far more than the sum of their sales data, of course. In our research, we also corralled information about what lies inside of each game. Check out the chart below to see the racing franchise's changing cast of characters, cups and courses.

For more on the latest entry, be sure to read Polygon's Mario Kart 8 review and watch it below.