We haven't had a US release yet.
Super Mario 3D World had a weak opening too, but sales got better a few weeks out. Yes that was holiday season.
Generally, Nintendo's games chart slow and steady over the long-haul, rather than the boom-bust pattern of many other game debuts. Though one can't deny the WiiU's other issues affect this circumstance.
Other than Pokemon, what was the last Nintendo game that went sky-high in the charts and moved tons of hardware?
I predict NX launches in 2017 - not 2016