In the last trading session, encouraging new-home sales data and better-than-expected European private sector manufacturing and services data led the U.S. benchmarks to close in the green. Among the top ETFs, investors saw (SPY Quick QuoteSPY - Free Report) gain about 0.2%, (DIA Quick QuoteDIA - Free Report) rise around 0.1% and (QQQ Quick QuoteQQQ - Free Report) increase about 0.2% on the day.

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

(IVOV Quick QuoteIVOV - Free Report) : Volume 4.25 times average

This mid-cap value ETF was under the microscope on Tuesday as nearly 103,600 shares moved hands compared to an average trading volume of 24,850 shares. We also saw some share price movement as shares of IVOV gained 0.6% today.

The movement came largely on the back of strong gains in the broader market. Moreover, the potential of mid-cap funds to offer best of both small- and large-cap funds also played an important role in boosting this mid-cap value ETF. For the month, IVOV gained 2%. The fund currently has a Zacks ETF Rank #3 (Hold).

: Volume 4 times average

This energy ETF was under the microscope on Tuesday as nearly 73,700 shares moved hands. This compares to an average trading day of 19,500 shares and it came as FRAK gained around 0.5% on the session.

The big move was largely the result of a strong gain in oil prices, which was the result of rising speculations that major oil producers may meet soon in order to control oil production.  FRAK surged 11.1% over the past one month.

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