Which Hong Kong stock index lost about 30% during the 1997 Asian financial crisis?

The Hang Seng Index lost about 30% during the 1997 Asian financial crisis.

Hong Kong's Hang Seng Index suffered a dramatic sell-off in October 1997. Between October 20 and October 23, the index fell about 23 percent, and its decline over the crisis period reached roughly 30 percent. The pressure reflected fears about currency stability, regional contagion, and the sustainability of high asset prices.

The Asian crisis began with Thailand's financial troubles and spread across several economies. Investors withdrew capital from countries with high foreign-currency debt, weak banking systems, or vulnerable exchange-rate arrangements. Indonesia, South Korea, Malaysia, and the Philippines were among the economies hit particularly hard.

The Hang Seng is Hong Kong's main stock-market benchmark, while the Nikkei 225 measures Japanese shares and the KOSPI measures South Korean shares. Those indexes also moved during the crisis, but the question's approximately 30 percent figure refers specifically to Hong Kong's Hang Seng Index.