Reuters tells us all about the “Hindenburg Omen” technical indicator:

Named after the zeppelin disaster that took place over Lakehurst, New Jersey, in 1937, the pattern is a “rare but potent” sell signal, said Jay Shartsis, director of option trading at R.F. Lafferty & Co.

For this to be activated, it requires at least 2.2 percent of the market to reach new 52-week highs and 52-week lows on the New York Stock Exchange on the same day, which happened yesterday, suggesting a lack of conviction among investors. However, it also needs to happen in a rising market, based on certain indicators, including a 10-week moving average of the NYSE Composite, which has to be rising.

Shartsis said the indicator “speaks for itself,” noting that when confirmed by a second occurrence within 36 days, “every crash (since 1985) was preceded by such a signal.”

Kind of a drastic name for what could pretty much just be indecisiveness among investors, or certain sectors being far more dogged than others — but if the market dies in a fire, don’t say the charts didn’t warn you.