There is a detailed description of how to get the info for all buckets in post #1 of this thread from the FAQ:
http://www.flyertalk.com/forum/unite...-each-one.html

If you only care about the revenue buckets then the flight details route mentioned above works.

Might find more info in one of these:
http://www.flyertalk.com/forum/unite...ad-merged.html
http://www.flyertalk.com/forum/unite...t-ual-com.html