You have a number of cars and each car is used as a 'pool car' during the workday. After the workday has finished, your employees can take a car home and back to work the next day. You have a policy (which you enforce for all your cars) that the only private travel that is permitted is this private travel to and from work.
Some employees travel on a toll road on the way to and from work. Electronic toll tags (accounts held in your name) are attached to each of your cars which record all road toll expenditure for each car.
During the work day, because of your car usage policy, each car is only used for business purposes and any road tolls incurred are otherwise deductible.
Because different employees are using different cars on different days and at different times, it would be difficult for you when examining, for example, electronic toll statements, to determine which trips were for private travel.
In this situation, you may be able to determine, for each employee who has regular access to a car for private use, what would be a normal to and from work road toll expenditure in a normal work week and apply this to the employee's working year.
Using this information and supporting evidence you can determine the total private road toll expenditure for all employees over the full year. This amount would be used as the taxable value.
Supporting evidence may include electronic tag records, running sheets and employee attendance records.