In the city of Seattle, for example, every year, companies over a certain number of employees are required to participate in an annual transportation survey. The employees are surveyed. The questions ask how far the employee commutes to work, how long it takes, and by what method (private vehicle, car pool, public transportation), how many days a year they work from home, or take off, etc. The effort is to assess the impact on environment, parking infrastructure, public transportation, roads, etc.
Obviously, there isn’t a 100% response rate so the data is extrapolated from the responses to the total number of employees employeed at that site (probably why they only poll companies of a minimum size and larger).
If they wanted to implement something like this in seattle, then the next step would be to take the data they already have and start sending those companies a new bill for a new annual tax based on the assessment.
Lots of taxes work off of an estimated assessment rather than having to account for every nut snd bolt of the thing (property taxes, for example).
So how do you do it? That’s how you do it. This isn’t rocket science, and you don’t need to invent new accounting methods or worry about the accounting-sky falling to accomplish it.