China Stokes a Stock-Market Mania, Risking Repeat of 2015 Bubble

The dramatic moves in Chinese stocks over the past week are inviting comparisons with a bubble that burst spectacularly five years ago.

In many ways, the pace of gains matches the market’s melt-up that started in the final weeks of 2014. The CSI 300 Index has now added 14% in five days, the most since December that year. A gauge of momentum on the CSI 300 is also the strongest since late 2014. Shares of brokerages surged as daily turnover exceeded 1.5 trillion yuan ($213 billion) for the first time since 2015, indicating increasing participation from retail investors. Monday’s more-than-5% gain in stocks had only happened once before since the bubble burst.