Investors watch the electronic board at a stock exchange hall in Shanghai, China. - 

The key stock index in Shanghai fell 5.3 percent today. The loss, the worst in 4 years, comes after China’s central bank froze lending between the country's financial institutions last week.

How ready are big banks around the world for the occasional financial crisis? In its annual report, the Bank for International Settlements in Basel, Switzerland, says central banks have done their part. Now it’s time for governments to do more.

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