Sounds like you have a project-based environment. Whether you are doing app dev, infrastructure dev or ops for either, projects are usually approved based on some value proposition process involving non-it management.
If they approved the project and associated costs to begin with, seems to me that if you are tracking time and come in on time and on budget, that means they are getting what was agreed to up front – which by default means they are getting their moneys worth based on that initial value prop process used to approve the project in the first place.
As far as how “productivity” compares to industry standards, for app dev you could look at function point metrics, for infrastructure you could come up with an ROI scheme of some kind etc.
Depending on the nature of your development efforts, you might find that the effort to measure to that function point degree of granularity represents a significant cost in and of itself.
I’d suggest that your money would be better spent implementing some continuous process improvement framework like CMM/CMMi.
Good luck! We’ve gone from the glamour of 1999 to being on everyone’s radar as a cost center . . . . bummer; but it?s where we are now!