I should have also added, what kind of trucks (gas/diesel) and on average what's the mpg?
For what I have calculated into my P&L so far, I'm at 6%. Only 1 truck and I avg 8-9 mpg and maybe 10 if a good amount of driving is highway. The best I have gotten was 12 and that was on a trip to the motocross track & back that is 140 miles away with just my bike in the bed. If I'm towing my toy hauler I get 7.5-8.