In the last trading session, the U.S. stocks managed to hold up gains as the Fed kicked off its crucial two-day meeting. Among the top ETFs, investors saw SPY gain 0.9%, (DIA - ETF report) rise 0.8% and QQQ move higher by 0.6% 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 ones to watch out for in the days ahead to see if this trend of extra-interest continues:

(IVOO - ETF report): Volume 5.9 times average

This mid cap ETF was in focus yesterday as more than 99,000 shares moved hands compared with an average of roughly 18,000 shares. We also saw some price movement as IVOO added 1% in the last session.

The movement can largely be blamed on an uncertain Fed policy that made investors cautious and shift to mid cap stocks. This is because these stocks generally offer the best of both worlds — allowing growth and stability in portfolios. For the past one-month period, IVOO was down nearly 4.2% and currently has a Zacks ETF Rank #3 (Hold).

(DWM - ETF report): Volume 2.6 times average

This international ETF was under the microscope yesterday as about 157,000 shares moved hands. This compares with an average trading day of around 67,000 shares and came as DWM gained 1.7% in the session.

The big move was largely the result of the looming interest rates’ hike decision that can have a big impact on the international stocks like what we find in this ETF’s portfolio. DWM was down 5.8% in the past one month and currently has a Zacks ETF Rank #3.

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