https://www.gamespot.com/articles/nintendo-switch-and-3ds-enjoyed-a-big-month-in-dec/1100-6456194/

Nintendo enjoyed a great deal of success throughout 2017 thanks to Switch, and that didn't change during December in the United States. Ahead of NPD Group publicly releasing its sales report for the month, Nintendo has shared some figures from it that paint a positive picture for not just Switch, but 3DS as well.