When will Mario Kart 8 surpass NSMBU in sales?

[Ryng]

Paatar said:

Ryng_Tolu said:

US, confirmed by NPD.

Europe numbers too seem too low...

I'm not asking by who, I'm asking by how much. :P

we can at least predict by how much, but is not official.

Nintendo confirmed 4,770,000 shipped by 31 December 2014. 

Assuming it is probabily at +5,000,000 now... maybe 200,000/250,000 undertracked?