Many airlines are reporting good or great growth in their earnings reports this quarter.

In this segment from the Industry Focus: Energy podcast, Sean O'Reilly and Tyler Crowe explain what the airline companies' metrics really mean, and why most of this growth we're seeing probably isn't as impressive as it first seems.

A full transcript follows the video.

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This podcast was recorded on April 22, 2016. 

Sean O'Reilly: Real quick before we move on. I'm interested to get your thoughts on the airlines. These guys have, you think, been an automatic beneficiary of low oil prices.

Tyler Crowe: Oh, and they have been.

O'Reilly: Immediately. Except for, who was it that had really high-priced hedges that hasn't really benefited?

Crowe: Sorry.

O'Reilly: No big deal. Anyway. You mentioned before we went on air that you had been looking through their results. Alaska Air (ALK 4.03%) and Southwest (LUV 0.97%) have reported. Some good and some bad.

Crowe: I wouldn't say I'd call it bad. More just like flat-lining. Very neutral. Some of the good things that you see, obviously the headline number says they made some of their best return on invested capital numbers. They made some of their best profit numbers in a quarter, which all sound great. Then when you start to break down what those are, some of the gains that you had. You saw a modest uptick in total miles flown, basically they're scheduling more flights. They're building out a little bit more few new routes, but they're very measured when it comes to those things. Their load factor, and this is an important metric when you're thinking about the airline industry -- load factor is basically how full the planes are at any given time. You saw a modest uptick in that. They're in the 80.4%-80.5%, which is right around where they were -- like I said, not even a full percentage point increase there. But improving.

The one thing that is interesting for both Alaska and Southwest was another important metric, which is PRASM, or passenger revenue per available seat mile. This is one of the most important metrics when you're looking at airlines because it's basically saying --

O'Reilly: So listeners should be writing this down.

Crowe: Right. That's the one that you really want to look at is how much revenue they're generating per seat on the plane per mile that's actually flown. That includes things like fuel costs and how full a plane actually is. It's a very important metric to actually keep track of. If you look at these companies, Alaska's was down a little bit, Southwest was very modestly up. Again, pretty flat-line numbers when we're looking at increases on things like this. It's kind of telling when you look at the big gains in terms of revenue or income that they got -- sorry, income, not revenue. And then look at the PRASM numbers, which are pretty modestly flat, you can pretty much kind of assume that a lot of these gains are coming from modest expansion in the company and a major benefit from oil and gas prices.