Which U.S. stock index lost nearly 78% from its 2000 peak during the dot-com crash?

The Nasdaq Composite lost nearly 78% from its 2000 peak during the dot-com crash.

The index reached an intraday high of 5,132.52 on March 10, 2000, as investors poured money into internet and technology companies. Many firms had little revenue or no profits, but optimistic expectations drove their share prices to extreme levels. When confidence weakened, technology stocks fell rapidly.

The Nasdaq Composite eventually reached a bear-market low of 1,108.49 in October 2002, a decline of roughly 78% from its peak. The collapse damaged technology companies, venture capital portfolios, and investors, although the internet itself continued to expand and later supported highly profitable businesses.

The Nasdaq Composite is broader than the Nasdaq-100 because it includes thousands of common stocks listed on the Nasdaq exchange. The dot-com crash is therefore not the same as a total collapse of all technology activity; it was a collapse in the valuations of many publicly traded companies.