These datas show that for 2019 the Switch is exploding only in Japan (+45-50%) and just having a noticable increase on other regions...I wonder if European and RotW numbers are not dramaticaly undertracked.
It makes sense that Japan is experiencing the biggest growth YoY. Seeing as how we're fresh off Let's Go and Smash Bros. in the holiday season + the lineup Nintendo has planned for 2019 is more focused on the Japanese market than the Western market. Yokai Watch 4, Super Mario Maker 2, Fire Emblem: Three Houses, Dragon Quest XI, Pokemon Sword/Shield, and Animal Crossing are all going to have notable hardware boosts in Japan, especially the latter 2.
As for the rest of the markets, NPD will show us just how much it is growing in the U.S. in a few days. Europe and the Rest of the World is the big question mar for sure. And since we don't have any consistent data figures like we do for the U.S. and Japan, we'll likely be stuck waiting for Nintendo to release their final figures for the Fiscal Year themselves at the end of April.
Pancho A. Ovies
Nintendo Switch in Japan (Famitsu): 2018 vs. 2019
PlayStation 4/Xbox One/Nintendo Switch: 2018 vs. 2019