In the last trading session, U.S. stocks were in the red. Among the top ETFs, investors saw (SPY Quick QuoteSPY - Free Report) losing about 1.5 %, (DIA Quick QuoteDIA - Free Report) shedding about 1.2% and (QQQ Quick QuoteQQQ - Free Report) move lower by over 2% on the day.

Two more specialized ETFs are also worth watching 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 of the last 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:

(VXX Quick QuoteVXX - Free Report) : Volume 3.83 times average

This S&P 500 VIX Short-Term Futures Index Total Return was in the spotlight yesterday as nearly 272.5 million shares exchanged hands compared with an average of roughly 71.1 million shares a day. We also saw great price movement as VXX gained about 16.3% last session.

The move was largely the result of a sudden flare-up in political uncertainty in the U.S., which gave a boost to VXX. The fund was up about 18.4% in one month.

(SDS Quick QuoteSDS - Free Report) : Volume 3.38 times average

This double-leveraged inverse S&P 500 ETF was under the microscope yesterday as about 8.2 million shares changed hands. This compares with an average trading volume of around 2.44 million shares and came as SDS added about 3.1% in the session.

The movement can largely be credited to the sell-off in the S&P 500 index thanks to some downbeat U.S. economic data and the disbanding of Trump’s American Manufacturing council. SDS advanced about 2.2% in the last one month.     

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