The Fiat 500L leads the list of vehicles that lose the most value, plunging almost a third in its first year.

One of a new car or truck’s most significant long-term ownership costs is depreciation, which is how much of its original value it loses over time. Aside from a brief period following the Great Recession when used-vehicle prices actually increased because of a serious supply shortage, new cars are almost always depreciable assets, with resale values that literally drop the minute after being driven off a dealer’s lot.

But resale value is the proverbial dual-edged sword. To the original buyer, a car that suffers a rapid rate of depreciation means taking a major hit to the pocketbook at trade-in time, while the same model can represent a bona fide bargain to a used-vehicle shopper. Generally, a new car or truck loses around 21 percent of its original sticker price after a year on the road, but the worst offenders in this regard lose a third or more of their resale values within the first 12 months of ownership.

According to a study of over 14 million new and used car transactions recorded over a one-year period by the auto-listing website iSeeCars.com, the model that loses the largest chunk of its original worth during Year One is the Fiat 500L subcompact wagon. It loses a budget-busting 34.6 percent of its initial value as a one-year-old used car, which amounts to a net loss of $7,608 on the base Pop version.

Though it has its merits, including a spacious cabin with unparalleled outward visibility, the aforementioned 500L is not only the brand’s slowest selling model (and by a wide margin), it gets rock-bottom marks for performance and reliability from Consumer Reports.

Still, iSeeCars’ list of the 10 current models having the worst one-year resale values is populated with some otherwise desirable rides from the likes of Volvo, Mercedes-Benz, and Jaguar for which resale values tend to be low for reasons that not always have to do with a model’s performance or durability. Often it’s a case of a vehicle that’s stuck in its final model year before being redesigned, or one that lags in sales within a particularly crowded and competitive market segment. At that, luxury vehicles tend to inherently lose their owners more money than cheaper models simply because there’s more to drop in the first place.

We're featuring the 10 new cars iSeeCars determined will lose the largest percentages of their original value after the first 12 months on the road in the accompanying slideshow.

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