Only an overly generous guess. BTCGarden managed to sell a lot, yeah. They had sold like almost a PH a month ago. let's assume they now sold 3. With all their 400 GH/s machines, ROCKMINER needs to sell like 4000 machines to achieve a single PH. Lightning Asic seems to be stagnating ever since. They even have a in-stock-counter that moves about 5 pcs/week. I doubt they sold more than 100 TH/s. Who else is there? XBTec used to be the big hope for AM. Well, they've gone silent, and only have lowered (as in 'it got worse') their consumption expectations. They really seemed to have done the trick in optimizing the BE200. I'm having a hard time reaching even those estimated 6 PH/s. And that would only account for 1/10 of those 60 PH/s
Hashratio and franchised mining seems to be the final straw. And I can't believe that FC is dictating the terms there 

Please show me calculations that support more chips have been sold to manufacturers!