(Bloomberg) -- The reckoning arrived for one of this year’s most popular trades.

Low-volatility stocks have gone wild in recent months, discovering the danger in the second part of their name and rattling investors who sought safety by sending $6 billion dollars to the biggest ETF that track them. Those flows have slowed as a measure of the group’s swings exceeds the broader markets, reaching levels not seen in 20 years, data compiled by Bank of America and Bloomberg show.

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