In the last trading session, U.S. stocks delivered mixed performance as data released on Friday showed the U.S. economy is gaining momentum, which in turn led to speculation of the Fed raising interest rates this year. Among the top ETFs, investors saw SPY lose 0.13%, DIA move higher by 0.07% and QQQ fall 0.16% 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:

(IEI Quick QuoteIEI - Free Report) : Volume 5.71 times average

This U.S. intermediate-term Treasury bond ETF was under the microscope on Friday as nearly 2.7 million shares moved hands. This compares to an average trading volume of 474,000 shares and came as IEI lost nearly 0.2% in the session.

The movement was because of rising U.S. Treasury yield. In the last one-month period, IEI was down about 0.1%. The fund carries a Zacks ETF Rank #3 (Hold).

(IJR Quick QuoteIJR - Free Report) : Volume 2.22 times average

This U.S. small-cap ETF was in focus yesterday as almost 1.9 million shares moved hands compared to an average of roughly 856,000 shares. We also saw some stock price movement as IJR was up about 0.3%.

The movement can largely be attributed to risk-on trade sentiment which probably led investors to consider small-cap stocks. With the U.S. showing signs of recovery amid global market turmoil, these small-cap ETFs with high domestic exposure have been gaining popularity. In the last one-month period, IJR was up over 5.5%. The fund carries a Zacks ETF Rank #3.

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