Denver is the 10th
busiest airport in the world in passenger movement.
Considering that Denver is a city with 2.7 million (18th largest metro in the nation) and has an O&D of over 50% for an extremely busy airport is really quite impressive.
Dallas is a huge city, and unlike Denver other airlines have a decent market share.
In DEN, United and United Express make up 64% of the marketshare which is a lot. Not sure what American Airlines makes up in Dallas. But there is considerable competition by other airlines to balance things out. That's not the case with Denver as much.
Also roughly 2 years ago, United had 78% of the marketshare in Denver which is crazy.
This was before the Frontier Airlines "boom" and the introduction of new airlines and further expansion by the majors.
Also, Denver's fares are among the highest in the country, MUCH higher than in Dallas which will of course greatly change the O&D figures. The average fare in Denver is 25% above the nations average.
Phoenix is swarmed by low-fare carriers Southwest, and America West and as a result O&D is also high there, even higher than Denver.
Those of you who tried to book a flight to Denver know what I'm talking about. Flying to Denver is expensive and many here in Colorado are always complaining about how high the fares are. That's why Coloradans are desperate for Southwest.
Of course, that would ruin Colorado's high-yield reputation.
"Generosity is giving more than you can, and pride is taking less than you need." - Khalil Gibran