Is China’s GDP Overstated By 60%?

I’ve long thought that, based on the fragmentary evidence we have (the huge debt load, the ghost cities, the known mismanagement and calculation problem of planned communist economies, etc.), the size of China’s economy is overstated by 40%. Now, according to the measurements of one pretty good proxy for economic activity, it appears that I was too trusting and optimistic about the size of China’s economy, in that it’s probably overstated by 60%.