That 10.62 comes from famitsu vol 306 but the cutoff is march 1996. It had Japan at 1.78M and overseas at 8.84 M thats a total of 10.62 millions. To that we have to add whatever Sega sold from the end of march 1996 to April 1997 and whatever Majesco sold when they got a license from sega to manufacture the Game Gear.
this IGN article says on the first line of the seventh paragraph: Yet, the machine did find an audience of approximately 11 million around the world.
Famitsu vol 306 21 Jun
Thank you. I'll pass it along. Again, not sure when the page will be updated. Other than 5 platforms we are still updating the figures to (XS, X1, PS5, PS4, and 3DS). The 3DS I do plan to stop tracking outside of Japan at the end of June with how low its figures now are. Only reason I will still keep posting 3DS numbers for Japan is due to Famitsu.