In the last trading session, U.S. stocks were slightly in the green. Investors were probably clueless about the growth momentum of the U.S. economy as manufacturing data for the month of August came in soft suddenly. Among the top ETFs, investors saw (SPY Quick QuoteSPY - Free Report) gain about 0.01%, (DIA Quick QuoteDIA - Free Report) add about 0.1% and (QQQ Quick QuoteQQQ - Free Report) advance about 0.3% 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:

(FXH Quick QuoteFXH - Free Report) : Volume 3.72 times average

This healthcare ETF was under the microscope on Thursday as nearly 532,666 shares moved hands. This compares to an average trading volume of 143,220 shares and came as FXH lost about 0.2% in the session.

The movement can be credited to ongoing issues over the pricing of drugs. In the last one-month period, FXH was down over 1.6%. The fund has a Zacks ETF Rank #2 (Buy).

: Volume 2.95 times average

This value ETF was in focus yesterday as roughly 18,000 shares moved hands compared with an average of roughly 6,000 shares. DVP lost about 0.1% on the day. However, in the last one-month period, DVP was up 1.8%. The fund has a Zacks ETF Rank #3 (Hold).

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