What was the main U.S. stock-market index associated with the 1929 Wall Street Crash?

The Dow Jones Industrial Average was the main U.S. stock-market index associated with the 1929 Wall Street Crash.

The Dow tracked 30 major American companies and was already a widely followed measure of industrial share prices. It reached a peak in September 1929 before falling sharply through October. The collapse included major selling days later remembered as Black Thursday, Black Monday, and Black Tuesday.

The crash was part of a much broader economic breakdown that became the Great Depression. Falling share prices damaged confidence, reduced wealth, and worsened financial distress, although the Depression had multiple causes, including banking failures, declining production, and weak international trade.

The Dow’s numerical level in 1929 should not be compared directly with today’s level without considering changes in the index’s construction and long-term economic growth. The S&P 500 did not yet exist in its modern form; it was introduced in 1957.