Dagong, the Chinese rating agency, has been claiming for a while that the US GDP is much smaller than $15 trillion:

“In the components of the U.S. GDP in 2009, the financial services sector accounted for 21.4%

while the real economy sector accounted for 65%.The total output value of the U.S.

financial services industry is composed of two major parts: one is the transferred

production value, most of which comes from value distribution of participating in

international production. Another part is the inflated value originated from credit innovation,

which belongs to bubble value. In addition, due to [...]