Here in Michigan we have a problem: the automobile industry. Thanks to foreign competition and the doubtful management of the Big Three, the state’s economy is in serious trouble. Should we just sell the state to the Chinese? There is a history of this in Michigan – we once traded the city of Toledo to Ohio in exchange for the upper peninsula. So perhaps it would be a good idea. But what would be a good price?
Mrs J, Michigan

Dear Mrs J.,

Make sure you don’t sell yourselves cheap. According to the US Bureau of Economic Analysis, Michigan’s GDP was $382bn in 2007. This is an attempt to measure the value added to all goods and services in Michigan, which includes anything from haircuts to assembling a car – but not, for instance, any components imported from out of state.

The $382bn figure is impressive. It would sneak Michigan into the top 25 economies in the world. Even China’s GDP is less than nine times greater.

So how much would it cost to buy $382bn of productive power? No corporation adds nearly as much value; the economist Paul de Grauwe reckoned that in 2000, value added was $67bn for Wal-Mart and $53bn for Exxon, the two largest companies. Their market value at the time was about five times their value added.

If the same ratio applies, buying Michigan would cost the Chinese almost $2 trillion –roughly what China’s State Administration of Foreign Exchange has to spend. All this assumes that Michigan’s residents, like Wal-Mart’s employees, would be free to leave if they didn’t like the new management.

Still, don’t hold out too long: even before the credit crunch hit, Michigan’s GDP per head was falling in real terms. This may be the right time to sell.

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