The hottest trade of the year could soon cool off

The Dow Jones Transports are on a tear this year, up 14 percent in 2014 and 30 percent over the last 12 months. That's far higher than its broader-market siblingthe Dow Jones Industrial Average, which has only gained 3 percent in 2014.

So is it too late to get in?

One portfolio manager says yes. Erin Gibbs, equity chief investment officer at S&P Capital IQ, believesthe train has already left the station for the transportation index.

"For the transports, I's too late," said Gibbs, who has about $11 billion in assets under advisory. "When looking at valuations and price targets, I really expect the transports to underperform the overall market over the next 12 months."

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However, Gibbs said airlines have some leadership within that group, particularly Delta and Alaska Airlines. "Rather than looking at the transports, I say either get an airline ETF or look at the underlying companies," she said. "There are some great winners in the airlines there."

Richard Ross, global technical strategist at Auerbach Grayson, believes the Dow Jones Transportation Average will ultimately be done in by the Dow Jones Industrial Average and will underperform the broader market index ahead.

"The key word is 'underperformance' not of the transports per se but of the industrials, curiously enough," said Ross, a "Talking Numbers" contributor. He sees a problem with the gap between two indices. "I think that performance gap comes in which would mean that those transports, just like Erin said, would underperform the industrials."

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Looking at a seven-year chart of the IYT, the ETF that tracks the Dow Jones Transportation Average, Ross sees a head-and- shoulders bottom pattern that formed a strong foundation for a breakout beginning in early 2013. Though it may not be the end of its rally, Ross thinks now is the time to get out of the sector and the ETF.

"The problem is we already had a very big part of that bull run – in fact, probably, the better part of it," Ross said. "So I would be a better seller up here."

To see the full discussion on the Dow Jones Transportation Average, with Gibbs on the fundamentals and Ross on the technicals, watch the above video.

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