Retarded question, but keep in mind there's only about 134 million registered domains. Doesn't mean all are active, just registered. Google's annualized Adsense revenue is about 9 billion, they pay out about 7.5 billion of that, 5 billion goes to revshare partners (our friends in the doubleclick ad planner) the remaining 1.5 billion is approportioned twixt about/no more than 750,000 Adsense plain vanilla publishers. Thus average Adsense income for average non-revshare Adsense publisher is $2000. So the average number of $2/day domains the average Adsense publisher might have is 3, so 2.25 million MFA's is a reasonable number that jibes with the % that represents of all registered plain TLD domains and Google's payout to the majority of publishers who don't make much.