About new GDP estimates

Comments on Arvind Subramanian “Is China already number one? New GDP estimates”, 3/02/2011, http://www.eastasiaforum.org/2011/02/03/is-china-already-number-one-new-gdp-estimates/

The size of the Chinese economy may be catching up with that of the America's in PPP terms, but it is probably not quite close to that point yet.

It is unclear whether your calculation is correct, given that some and possibly a large portion of the Chinese growth from 2005 to 2010 is from tradable sector - it implies that its PPP growth should be lower than its headline GDP growth.

If my reasoning is correct, then the part you didn't say but probably used in your calculation may have overstated China's PPP level.