please explain

Trying to get my sad tired brain around some relenza figures.

Production is expected to be 190m doses, but lets be conservative and say 170m (20m freebies) x $25 per dose = 4,250m x 7% = $298m in royalties

but the other info gsk is reporting is that they expect 600 pounds, say $1,200m x 7% = $84 mill

What am I missing? Is it the lag to ramping up production or does the new delivery method produce lower revenue? Any clues anybody?

cheers