In the last trading session, U.S. stocks saw a tumultuous ride as the spread of the highly contagious Delta variant of coronavirus in the United States with the lowest vaccination rates has raised concerns over the sustainability of economic recovery. Among the top ETFs, (SPY Quick QuoteSPY - Free Report) shed 0.8%, (DIA Quick QuoteDIA - Free Report) lost 0.7% and (QQQ Quick QuoteQQQ - Free Report) moved 0.6% lower 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.

(PNQI Quick QuotePNQI - Free Report) : Volume 3.49 Times Average

This Internet ETF was in the spotlight as around 64,000 shares moved hands compared with an average of 18,000 shares a day. We also saw some price movement as PNQI lost 1.4% in the last session.

The move was largely the result of a resurgence in demand for e-commerce triggered by the global growth worries. This could have a big impact on Internet stocks like the ones that we find in this ETF portfolio. PNQI has gained 5.5% over the past month and carries a Zacks ETF Rank #3 (Hold) with a Medium risk outlook.

(IUSV Quick QuoteIUSV - Free Report) : Volume 2.99 Times Average

This value ETF was under the microscope as nearly 1.6 million shares moved hands. This compares with an average trading volume of roughly 528,000 shares and came as IUSV lost 1% in the last trading session.

The movement can largely be blamed on growth worries returning the appeal for value ETFs. IUSV has tumbled 2.9% in a month’s time. It has a Zacks ETF Rank #1 (Strong Buy) with a Medium risk outlook.

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