Which U.S. stock-market index lost almost half its value during the 1929 crash and subsequent bear market?

The Dow Jones Industrial Average lost almost half its value during the 1929 crash and the bear market that followed.

The Dow peaked at 381.17 on 3 September 1929. After a series of dramatic declines, it reached a low of 41.22 on 8 July 1932, a fall of nearly 89% from its peak. That collapse unfolded alongside the Great Depression, although the stock-market crash alone did not cause every part of the worldwide economic crisis.

The Dow was a price-weighted index of major U.S. companies, so its movements reflected the share prices of its component firms rather than the total market value of all listed companies. The S&P 500 did not yet exist in its modern form.

The market eventually recovered, but the Dow did not regain its September 1929 closing high until November 1954. This long recovery period is one reason the crash remains a central reference point in financial history.