Which stock index was the main measure of the United States market during the 1929 Wall Street Crash?

The Dow Jones Industrial Average was the main measure of the United States stock market during the 1929 Wall Street Crash.

The Dow, created by Charles Dow and first published in 1896, tracked a small group of major American companies. In 1929 it contained 30 stocks, as it does today, although its components and calculation method have changed substantially over time.

Newspapers and historians used the Dow to describe the market’s rise before the crash and its collapse afterward. The index reached a then-record closing level in September 1929, then fell sharply through October and November. Its recovery to the pre-crash high took many years.

The S&P 500 did not exist in its modern form in 1929, and the Nasdaq was founded decades later. Those indexes are important modern benchmarks, but they cannot be substituted for the Dow when describing the standard market measure used in accounts of the 1929 crash.