A major Chinese stock-market benchmark sank to its lowest level in more than four years, signaling deep pessimism among global and domestic investors in the country. 

The CSI 300 index, which is made up of shares of the most valuable companies listed in Shanghai or Shenzhen, dropped 1% on Monday to a closing level last seen in February 2019. It was a fourth consecutive day of declines for the benchmark, which has lost more than 10% this year.