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The Hindenburg Omen is a combination of technical factors that attempt to measure the health of the NYSE, and by extension, the stock market as a whole. The goal of the indicator is to signal increased probability of a stock market crash.

The rationale is that under "normal conditions" a substantial number of stocks may set either new annual highs or new annual lows, but not both at the same time. As a healthy market possesses a degree of uniformity, whether up or down, the simultaneous presence of many new highs and lows may signal trouble.