China as Number One

Most of the reporting on China and its current economic problems refers to it as the world's second largest economy. This is true if its GDP is measured on a currency conversion basis, in other words taking its GDP and effectively converting it into dollars at the official exchange rate.

However economists more typically use purchasing power parity measures of GDP. These involve using a common set of prices for goods and services in all countries. By this measure China's GDP is already more t...