“We think the increased usage of USMV by institutional investors has been a positive for all investors,” Rosenbluth added. “The average daily trading volume in the past month spiked to 3.3 million, up from 2.0 million during the past six months. The bid/ask spread is $0.01, lower than most ETFs.”

The PowerShares S&P 500 Low Volatility Portfolio (NYSEArca: SPLV) is the main competitor to iShares’ USMV. SPLV, though, simply tracks the 100 least volatile stocks taken out of the S&P 500. SPLV dropped 3.9% year-to-date.

iShares MSCI USA Minimum Volatility ETF

Max Chen contributed to this article.