S.Peelman on 28 February 2014
According to VGC numbers, first weeks and hardware at the time:
Donkey Kong Country Returns Wii: November release; US: 471k - EU: 150k - JP: 169k, Wii at 76.2m
Donkey Kong Country Returns 3D: May release; US: 73k - EU: 37k - JP: 102k, 3DS at 31.4m
Donkey Kong Country Tropical Freeze: February release; US: 109k - EU: 50k - JP: 38k, WiiU at 5.8m
Make of this what you will, personally I only see concrete evidence that the Japanese sales are bad, yet the low American and European numbers could very well just be due to install-base and an unfavorable release date which means this game will have legs. Moreover we don't know how it did digitally, though I know we shouldn't count on it making a considerable difference 
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