How can you "assume" All subscribers only purchase minimum subscription ($8.99/month)????
I for one have the 2 for $12.99 plan. A better "assumption" might be that singles would be more apt in getting the $8.99 plan. However, I would "assume" that families or couples would either subscribe with the 2 or 3 plan to satisfy everyone.
Maybe being an analyst, I'm being a little on the "anal" side but I would bet your #'s are wayyyyyyy off!