In the last trading session, U.S. stocks were mixed. Among the top ETFs, investors saw (SPY Quick QuoteSPY - Free Report) losing about 0.1%, (DIA Quick QuoteDIA - Free Report) adding about 0.3% and (QQQ Quick QuoteQQQ - Free Report) move lower by over 0.4% 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:

(HYD Quick QuoteHYD - Free Report) : Volume 4.76 times average

This high-yield muni bond ETF was in the spotlight yesterday as nearly 2.4 million shares moved hands compared with an average of roughly 500,000 shares a day. We also saw some price movement as HYD gained about 0.2% in the last session.

The move was largely the result of a decline in U.S. Treasury yields, which gave a boost to demand for high-yielding muni bond ETFs like HYD. The fund was up about 1.4% in the last one month.

(VUG Quick QuoteVUG - Free Report) : Volume 3.41 times average

This large-cap growth ETF was under the microscope yesterday as about 2.2 million shares changed hands. This compares to an average trading volume of around 657,500 shares and came as VUG lost about 0.3% in the session.

The movement can largely be credited to the political debacle related to Trump’s proposed pro-growth policies. Since there were no major legislative achievements in the first six months of the Trump presidency, some investors may have chosen to shift away from growth ETFs. However, VUG advanced about 2.8% in the last one month.     

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