I decided to do a chart to look at how you might view Wii sales throughout 2009 while attempting to eliminate seasonal trends from the picture. They're not fully eliminated, and other things would still affect the graph such as major releases in both 08 and 09, and shortages, but it should be mostly eliminated.
If anyone is interested, here it is:
Possible events that impact the graph:
Early 2008 had major releases like Mario Kart Wii and SSB:B, they would be responsible for a couple of the negative spikes in early 09.
Dec 2008 had shortages that may make Dec 09 look more impressive.
Wii Sports Resort first released on week 26, with bigger regional releases on week 30. If it had any long term impact on momentum, it is not immediately noticeable.
Monster Hunter Tri released on week 31.
Wii had a $50 price cut week around week 40. A short term effect is clear, the long term effect is not easily apparent, though it at least prevented Wii from being as badly in decline as it was for most of 09.
NSMB released on week 47. For the period after it's release Wii is strongly up year on year again. An alternative hypothesis to the effect is that Wii would have been lower YoY if not for shortages in Dec 08. We'll see which was the bigger factor as we go into 2010, as shortages were not an issue in January 09.
If anyone is interested I could improve the graph by adding in other consoles and adding in 2008 for a longer term view...
A game I'm developing with some friends:
www.xnagg.com/zombieasteroids/publish.htm
It is largely a technical exercise but feedback is appreciated.
