Car Depreciation Calculator Help With Car Depreciation?

Help with Car Depreciation? - car depreciation calculator

I have a program auto company, where I received more than $ 640/month for my car, more gas at $ .15/mile, tires and brakes and maintenance. I drive an average of 4700 miles per month and I feel bad business to this point, because the mileage is devalued my car very fast. Has anyone a calculator, such as the impact on the mileage and the value of what the impact of the depreciation rates for mileage. Any help or comments appreciated.