The World Bank PPP numbers will be updated in 2013. The International Comparison Program (ICP) is being implemented as a true global initiative for the second time, with the reference year 2011.
The ICP survey framework for household consumption prices will be reviewed to enhance the quality and consistency of household survey data, better delineate urban and rural areas wherever applicable, improve spatial pricing and geo-referencing sampled outlets.
This suggests that they will fix the problem of only sampling some urban cities in China, which may mean their numbers will be more in line with the Penn World tables 7.0 which will show that China is the worlds largest economy on a PPP basis.
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