Prepare to be unsurprised: The U.S. West Coast features the highest proportion of hybrid and electric vehicles across the country--with almost one in ten new vehicles sold in the San Francisco metropolitan area alone a hybrid.

That's according to research group Polk, which warns that generalizing about the U.S. new vehicle landscape as a whole is risky, when distinct sales patterns occur in certain areas.

The research suggests that 15 Designated Market Areas, or DMAs, with the highest percentage of hybrid powertrains account for 30 percent of the country's overall hybrid sales.

All 15 of those DMAs are located on the West Coast, with the San Francisco, Oakland and San Jose area accounting for the largest proportion.

While these areas feature the highest hybrid and electric sales, they make up only 12.5 percent of all new vehicle registrations, in the first ten months of 2012.

National penetration for hybrid vehicles stands at 2.97 percent, while San Francisco's hybrid market makes up 9.4 percent of all vehicles sold. A further 0.52 percent are electric.

The fifteen lowest-ranked markets for hybrids and electric cars are all in the central region of the country.

Proportionally, Tulsa features the lowest market penetration for hybrids, at only 0.58 percent of its 524,021 vehicles in the first ten months of 2012.

With incentives and regulations making hybrid and electric vehicles a more attractive option in California and Oregon, it's no surprise to see them topping the table as the most hybrid-friendly areas--and even less surprising that most hybrid and plug-in vehicles debut there before other markets.

Is your local area in the top or bottom 15? Let us know in the comments section below.

[Hat tip: Brian Henderson]


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