Which U.S. stock index fell nearly 80% from its March 2000 peak during the dot-com crash?

The Nasdaq Composite fell nearly 80% from its March 2000 peak during the dot-com crash.

The Nasdaq Composite reached a record closing level of 5,048.62 on March 10, 2000. The index contained many technology and internet companies, making it especially sensitive to the speculative enthusiasm surrounding the early web economy.

Investors had pushed the prices of many firms far beyond what their revenues or profits could justify. When confidence changed, technology shares fell rapidly. The Nasdaq eventually lost about 78% of its value from its peak to its October 2002 low.

The crash did not mean that the internet itself was a failure. Several companies disappeared, but others survived and later became major businesses. The episode is often confused with the broader 2000–02 bear market, which also affected traditional companies and other indexes. The Nasdaq’s technology-heavy composition explains why its decline was much larger than the fall in the Dow Jones Industrial Average.