Investors ignore the yield to worst at their peril, said Andrei Costas, a senior investment analyst at Avidian Wealth Management LLC, which sold its holdings in the ETF in February.

“Changing the yield to worst can change the return profile. It factors into an investor’s decision whether to buy or sell a fund,” Costas said. For the PowerShares Preferred Portfolio, the yield to worst is less than a third of the distribution yield.