What is the formula used to calculate the total annual mileage for a car?

The total annual mileage for a car can be calculated using the formula: Total Annual Mileage = Average Daily Mileage × Number of Days Driven per Year. To find the average daily mileage, you can track the distance driven over a set period and divide it by the number of days in that period. Multiply the average daily mileage by the total number of days the car is driven in a year (typically 365, unless factoring in days the car is not used).