Motor Club AAA has published a pamphlet called Your Driving Costs since 1950. The pamphlet lists a variety of factors that contribute to a vehicle's average cost per mile to drive, and it can be quite useful when you find yourself wondering if you really want to drive to the store when you can order your purchases online and have them shipped instead.

Often, the sole obstacle to my buying things online — aside from the occasional desire to physically inspect the item I'm purchasing before I buy it — is the cost of shipping. After all, why would I pay $5 to have something shipped when I can pick it up at the store free of charge? That's where the Your Driving Costs pamphlet comes in handy.

The vehicle my wife and I normally take on our shopping trips, for instance, is our 2006 Jeep Grand Cherokee, which would fall under the 4WD Sport Utility Vehicle category in the pamphlet and which — given the 20,000 miles or so we likely drive it per year — is estimated to cost us roughly 63 cents per mile to drive. Considering we do most of our shopping at stores on S. Westnedge Avenue in Portage, about 11 miles from our home, that comes to just under $14 for a round trip.

This number seems incredibly high, but it takes into account both operating costs (gas, maintenance and tires) and ownership costs (full-coverage insurance; license, registration and taxes; etc.). But even if you calculate just the estimated cost of gas per mile — 17.04 cents — that's still nearly $4 for a round trip.

Given that standard shipping starts at $5.95 at

, as just one example — with free standard shipping when you spend $75 or more — it's likely worth it for us just to buy online and save ourselves the time of driving out there. We would more than likely be saving money in the process.

One way we could save even more, obviously, would be by driving a less expensive car. Other average costs per mile for cars driven 20,000 miles per year, for instance, are 38.1 cents per mile for small sedans, 48.6 cents per mile for medium sedans and 61.2 cents per mile for large sedans. Download the PDF version of AAA's 2011 Edition of Your Driving Costs for more:

Tally up the costs per mile for your most common shopping trips. Does it make more sense to buy online and pay shipping? Let us know your thoughts in the comments section below or email me at

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