It's painful having to shell out $40 or more every time you go to the gas pump. Gas prices have tripled in the past decade and don't show signs of stopping anytime soon. But gas isn't the only expense you have to pay for the privilege to drive a car. Once you factor in insurance, the purchase price for your car, maintenance and all other factors, how much does that round trip to work really cost you?

It may make you sick to your stomach when you see $3.62 for gas on the sign, but when you factor in all the other charges related to driving, it's likely to give you a heart attack. For the average American who buys a new car, drives it for 5 years and sells it; $13.04 per gallon is the total cost of driving. Don't believe me? Lets take a look at how I came up with that average. Here are the factors I considered:

* Average new vehicle purchase price: $28,400 ? Federal Trade Commission

* Average resale value after 5 years: $9,940 ? AOL Autos

* Average miles driven in a year: 12,000 ? Environmental Protection Agency

* Average miles per gallon: 24.6 ? Wikipedia

* Average cost per gallon: $3.62 ? CNN Money

* Average annual car insurance: $829 ? Insurance Information Institute

* Average maintenance costs: $120 ? Four oil changes at $30 each.

Ok, I know it's a lot of math, but stick with me on this part. The easiest way to figure out how much you page per gallon is to figure out the cost of ownership for the full 5 years and divide that by the number of miles driven. This will give you the total cost per mile which you can multiple by miles per gallon to get the total cost per gallon. Here we go:

* Vehicle depreciation: $18,460 ? $28,400 new price, minus $9,940 resale price

* Gas: $8,829.27 ? 60,000 miles / 24.6 MPG * $3.62

* Insurance: $4,145 ? $829 a year * 5 years

* Maintenance: $600 - $120 a year * 5 years

* Total 5 Year Cost: $32,034.27

Now take that 5 year cost of driving and divide it by the number of miles driven and you come up with $0.53 per mile. Multiply that by 24.6 MPG and the result is $13.04 per gallon is the total cost of driving.

Of course the numbers will vary greatly, but on average that is what we are paying to drive. Plug in your own numbers and see what you come up with. Some additional factors you may want to consider factoring in are tag/title/tax, parking and tollbooths.

There are several steps you can take to reduce your total cost per mile. With a little over half of the total cost of driving coming from vehicle depreciation, the biggest step you can take is buying a used car and driving it much longer before selling. The trade off will likely be you pay much more on maintenance, but in most cases you'll come out ahead. You can also buy a more fuel efficient car. Finding the right used, fuel-efficient car may also allow you to save on insurance. By making these changes, you probably won't be the coolest kid on the block, but you just might be the richest.