Judging by the table, the switch need to sell around 200k in january and feburary each, to stay ahead of Wii and PS4. Not sure how realistic that is in the worst months of the year, but it certainly doesn't seem undoable.
They aren't the worst months of the year. Both belong to the better non-holiday months despite being four-week-periods and successful consoles have cleared the 200k mark in each month with ease in the past. It would be concerning if Switch finished below 500k combined for those two months.
EDIT: Looking through old NPD threads, the PS4 only failed once to exceed 200k in January, but that occasion was followed up with 340k in February. February is generally the stronger month because of tax returns in the USA.Last edited by RolStoppable - on 04 January 2018