Nintndo gives proof of third party Wii sales.

[Oyvoyvoyv]

Comparing the numbers to VGC:

Wii

For the entire Americas

Total: 77.5M

1st party: 41.6M

Total: 35.9M

If we say 10%, the OP says 33-34M. But, I have used 0.5 months extra (Wii launched in the middle of one) so they're spot on.

For Ps3:

Total: 33.7M

1st party: 7.1M

3rd party: 26.6M

So their data on Ps3 is incorrect. We have no valid X360 data, so I ignore it.

They undertracked Ps3 probably - on purpose.