In the last trading session, U.S. stocks were mostly in the green. Among the top ETFs, investors saw (SPY Quick QuoteSPY - Free Report) adding about 1.6%, (DIA Quick QuoteDIA - Free Report) gaining about 1.4% and (QQQ Quick QuoteQQQ - Free Report) move higher 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.

(TDTF Quick QuoteTDTF - Free Report) : Volume 3.61 times average

This Treasury Inflation Protected Securities ETF was under the microscope yesterday as about 578,409 shares changed hands. This compares to an average trading volume of around 160,220 shares and came as TDTF added about 0.3% in the session.

As inflationary expectations rose, this TIPS fund benefited. The fund lost about 1% in the last one month.

(VNQI Quick QuoteVNQI - Free Report) : Volume 3.10 times average

This international real estate ETF was in the spotlight yesterday as nearly 1.4 million shares moved hands compared with an average of roughly 463,410 shares a day. We also saw some price movement as VNQI advanced about 1.3% in the last session.

The move was largely the result of a broad-based market recovery. The fund was down about 6% in the last one month.

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