UPS said this week that it will cost 4.9% more in 2016 to ship a package by UPS in the United States. Sure, fuel costs are down, but it still costs money to operate a business such as UPS or a field services business where a lot of driving is involved.
The point I am trying to make is that maybe you should ask for 4.9% increase in what you charge for field services. What do you think? When is the last time you got a pay raise?