Trek has a section on airfoil drag around page 22-24 here:http://www.slowtwitch.com/Downloads/TK1 ... _lores.pdf
It's important to remember that manufacturers choose tubes shapes based on many things like:
1. yaw angle they feel is most important; i.e. Cervelo uses "sharper" airfoils in belief that lower yaw angles are more representative of real world conditions; Trek and Specialized tune their bikes more to ~10-12 degrees of yaw
2. location on bike
3. stiffness/weight/aerodynamic tradeoffs
Casper's chart only tells us a small part of the story, like is that only at 0 degrees of yaw, or and average? I would wager it's only 0 degrees of yaw.
Anyway, if you are trying to design a bike, hire someone to do some CFD and look at companies who know their stuff.
If you are shopping and want to be educated, I would say for time trial bikes there are some good parameters to help guide a purchaser:
1. down tube and seat tube under 30mm wide and over 75mm deep for the majority of their length
2. headtube under 40mm for the bulk of it's length and at least 3:1 depth with blending to downtube and top tube
3. non round, "aero" seatstays and fork