just a note of caution: one **** driver and all your calculations go to **** regardless how precise they were calculated.

second - working applications vary much, so any figures somebody gives you - will be misleading...

third - depends what you calculate in and what is left out..

fourth - depends on age of truck, service level, time frame used for calculations, human factor, climat, quality of fuel (if any) and other factors.. and a lot of assumptions...

Hope I din't disappoint you :-)