In the last trading session, U.S. stocks saw rough trading, following weak retail and industrial data. Among the top ETFs, (SPY Quick QuoteSPY - Free Report) lost 2.1%, (DIA Quick QuoteDIA - Free Report) shed 1.9% and (QQQ Quick QuoteQQQ - Free Report) moved 1.01% lower on the day.

Two more specialized ETFs are worth noting as both saw trading volume that was far outside of normal. In fact, both these funds experienced volume levels that were more than double their average for the most-recent trading session. This could make these ETFs the ones to watch out for in the days ahead to see if this trend of extra-interest continues.

(IEZ Quick QuoteIEZ - Free Report) : Volume 3.52 Times Average

This energy ETF was in the spotlight as around 419,000 shares moved hands compared with an average 138,000 shares a day. We also saw some price movement as IEZ plunged 6.2% in the last session.

The move was largely the result of sliding oil price to the lowest level in two decades that could have a big impact on energy stocks like the ones that we find in this ETF portfolio. IEZ has risen 30% over the past month and has a Zacks ETF Rank #5 (Strong Sell) with a High risk outlook.

(IWC Quick QuoteIWC - Free Report) : Volume 2.92 Times Average

This small-cap ETF was under the microscope as nearly 237,000 shares moved hands. This compares with average trading volume of roughly 84,000 shares and came as IWC declined 4% in the last trading session.

The movement can largely be blamed on disappointing data that led to risk-off trading. IWC has gained 21.2% in a month’s time and has a Zacks ETF Rank #3 (Hold) with a High risk outlook.

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