This has basically become the "pattern" right?
There is one "big" Wii U game during the first 6-8 months of the year -- Pikmin 3 (2013), Mario Kart 8 (2014), and Splatoon (2015). The first half of the year for the Wii U basically every year is one big extended drought with an oasis on a single big release around spring/summer time.
Then you get your "big" fall title and a couple of games around that ... Mario 3D World (2013), Smash U (2014), and Mario Maker (2015).
I guess Europe got Yoshi's Wooly World this year a bit earlier.