Gregory noted that in the investment potential category, every airline ranked below the averages for the transportation sector, the industrial sector and the entire list of companies.

"In this particular industry, it's very clear (that is) what the issue is," Gregory said. "Here you have a tremendous consumer product, but (investment potential) is one measure of it."

The highest rated brand, by the way, is Coca-Cola ( KO). Like Delta, Coke is based in Atlanta, but over the years, it has been perceived to be a great investment.

Funny thing, though. Year to date, Delta shares are up 65% and Coke shares are down 5%.

-- Written by Ted Reed in Charlotte, N.C.

>To contact the writer of this article, click here: Ted Reed

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