I printed out that nifty chart this morning and my husband told me that he had something better... if your CompuTrainer came with Cycling Peaks WKO + software you can analyse your workouts and it will show you where you lie in the scheme of things (cat 5/4/3 etc... ). This program is a bit more harsh than the chart above though

The software is not terribly intuitive though...... to get a workout in you have to drag the file onto the desktop icon for WKO+, then I had to close and save my athlete file and reopen it before the workout showed up, then there is a little magenta icon at the top of the screen that shows you your workout v/s the chart (blue of boys, change it to girls and its pink....)