Residential VoIP in USA

Somebody did send me the following link: In-Stat Reports 7.9 % of U.S. Households Now Use a VoIP Telephone Service

I will not reproduce the whole article (read it, quite interesting!), but made a graph with the data:

Nice, Skype in the first position!

Some remarks:

• They say 9 million households use VoIP
  
• This means more then 9 million persons
  
• My guess: 2.5 persons per household (?)
  
• 2.2 million Skype Households in the USA
  
• Therefore about 5.5 million Skype Users in the USA?
  

Also interesting: “more than 40 % of client-based VoIP users use their residential VoIP service either in part or in whole for business purposes”