Similar to wise buying decisions, exiting certain underperformers at the right time helps maximize portfolio returns. Selling off losers can be difficult, but if both the share price and estimates are falling, it could be time to get rid of the security before more losses hit your portfolio.

One such stock that you may want to consider dropping is P.A.M. Transportation Services, Inc. (PTSI Quick QuotePTSI - Free Report) , which has witnessed a significant price decline in the past four weeks, and it has seen negative earnings estimate revisions for the current quarter and the current year. A Zacks Rank #5 (Strong Sell) further confirms weakness in PTSI.

A key reason for this move has been the negative trend in earnings estimate revisions. For the full year, we have seen 1 estimate moving down in the past 30 days, compared with none upward revisions. This trend has caused the consensus estimate to trend lower, going from $2.60 a share a month ago to its current level of $2.16.

Also, for the current quarter, P.A.M. Transportation Services has seen 1 downward estimate revisions versus 0 revisions in the opposite direction, dragging the consensus estimate down to 70 cents a share from 91 cents over the past 30 days.  

The stock also has seen some pretty dismal trading lately, as the share price has dropped 21.9% in the past month.

So it may not be a good decision to keep this stock in your portfolio anymore, at least if you don’t have a long time horizon to wait.

If you are still interested in the Transportation sector, you may instead consider a better-ranked stock - Danaos Corporation (DAC Quick QuoteDAC - Free Report) . The stock currently holds a Zacks Rank #1 (Strong Buy) and may be a better selection at this time.

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