Which U.S. stock-market index lost nearly 90% from its 1929 peak to its 1932 low?

The Dow Jones Industrial Average lost nearly 90% from its 1929 peak to its 1932 low during the Wall Street Crash and the wider Great Depression. The index reached a pre-crash peak in September 1929 and eventually bottomed in July 1932.

The crash itself unfolded over several dramatic trading sessions, including Black Thursday on October 24, Black Monday on October 28, and Black Tuesday on October 29. The collapse followed years of speculative buying, widespread use of borrowed money, and growing weaknesses in the U.S. economy.

The Dow did not return to its 1929 peak until 1954. That long recovery period is one reason the episode remains a benchmark for discussions of bubbles and market risk. The crash did not single-handedly cause every feature of the Great Depression, but it intensified economic distress and damaged confidence.

The S&P 500 and Nasdaq did not yet exist in their modern forms, so the Dow is the principal index associated with the period.