Train wreck on 18 May 2018
For the year that the Wii shipped 20 million world wide this is what the NA shipments and US NPD sales looked like:
Wii 20 million (3-31-2009 to 3-31-2010)
Q1 Shipments 1.14M (NPD Apr-340k May-289.5k June-361.7) shipment sales difference +148.8k
Q2 Shipments 1.45M (NPD July-252.5 Aug-277.4 Sept-462.8) shipment sales difference +457.3k
Q3 Shipments 4.23M (NPD Oct-506.9 Nov-1260 Dec-3810) shipment sales difference (-1347)
Q4 shipments 1.48M (NPD Jan-465.8 Feb-397.9 Mar-557.5) shipment sales difference +58.8k
