Respected by many market veterans, the omen is triggered when, among other things, multiple stocks set new 52-week highs and lows simultaneously.
The phenomenon happens if both highs and lows are greater than 2.2 percent of the total issues that trade that day. That would translate into about 73 stocks each way.
In Friday's trading, there were 156 new lows and 90 new highs, according to Thomson Reuters.
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At its core, the Hindenburg Omen reflects market volatility—violent moves in either direction that are triggered during times of uncertainty.
Fund flows have reflected investor unease.
Last week marked 2013 lows for inflows into both stocks and bonds, while money market funds took in $13.1 billion, according to Thomson Reuters.