To well understand the field “margin” (in euro)

If I well understood the margin is calculated as the rate of the difference between validated cost and reassessed cost, that is (validated cost-requested cost)/validated cost.
This margin take only account the costs.
Is it possible to have a view of the margin regard to the revenue (turnover, “chiffre d’affaire” in French) ?
For instance I have a project with a budget or revenue of 1000 Kilo Euro and my estimated cost is 600 KE. The most of the time it is interesting to have a point of view of the gross margin or contribution that is calculated as : (assessed revenue – assessed cost)/ assessed revenue.
In my example gross margin or contribution is (1000-600)/600=40%
Thank by advance for any precision.
Eric

Ok thank you very much for your reply that confirm my filling. So you can have a view of the margin regard to cost or revenue (of the initial budget) but not the both.
Thank
Eric