Comparing per capita purchasing power is not useful. The sheer population of China makes it possible that China eventually surpasses America in every way (number of consumers, engineers, doctors, scientists, etc..)

There are two countries within China — the rural poor that earn $100/month and the urban rich with purchasing power that rivals America. The urban class is swelling to match the population of the US.

Look at Macao. It has surpassed Las Vegas in revenue in the last 5 years with all the major American casinos represented there. That’s testament to the Chinese’s purchasing power.