A monthly breakdown for the 3 months covered by this NPD statement would be more useful than this piece of information.
40GB model arrived on the market in November so only on sale for 2/3 of time covered by NPD statement. How the 80GB and 40GB sold over the 2 months when both were available would clarify if the 80GB unit was more popular than the 40GB, and by how much if it outsold it over that period.
1
A monthly breakdown for the 3 months covered by this NPD statement would be more useful than this piece of information.
40GB model arrived on the market in November so only on sale for 2/3 of time covered by NPD statement. How the 80GB and 40GB sold over the 2 months when both were available would clarify if the 80GB unit was more popular than the 40GB, and by how much if it outsold it over that period.