Another flaw in the whole calculation is the money conversion thing.
Cthulhudreams compares the income of an average US household to the price of a middle lifestyle for a family of four. In Germany we have a saying: "Birnen und Äpfel vergleichen". Comparing pears and apples. Those two values aren't comparable at all. There are far too many assumptions in this.
1) The number of people in an average US household. Is it really four?
2) The assumption, that the average US household can afford the equivalent of a middle Shadowrun lifestyle. The average Shadowrun Seattle household with four children can't, according to New Seattle.