Stock market bonanza is a worrying sign

Have Chinese shares been flying too high? Or, is the ongoing surge in stock prices just the beginning of a super rally toward a new record?

These questions must be weighing heavily on the minds of not only domestic investors who are opening new brokerage accounts by the millions every week, but also Chinese policymakers who reportedly expect a moderately bullish stock market to help overall economic growth.

The benchmark Shanghai Composite Index increased 1.54 percent to end at 5,023.1 points on June 5. It was the first time in more than 7 years that the index climbed above the psychologically important mark of 5,000 points since the Chinese stock market crashed from a historic high of 6,124 points in late 2007 to 1,664 points over the span of one year.