More than a month has passed since the Shanghai stock market plunge sent shock waves throughout global markets in late February. Although share prices have since stabilized, volatility rife in foreign-currency markets, with the dollar-yen rate sometimes fluctuating nearly 2 yen a day.

Stock markets are prone to synchronized global downturns when new types of shock arrive. But it should be noted here that the biggest factor behind the markets' recent problems is excess liquidity.

Even in a global chain reaction, different reasons particular to each country work to push down share prices, and the size of the decline varies.